Hello you guys!
I just received my lg g7 g710ulm. And when i turned on the phone i understood that im not lucky.. I need your helps! Please! Because i cant do it myself.
1. No signal. Don't search networks. Immediately getting error when trying to do it myself. "Preferred network mode" can't change due error and it showed "null". After reflashing it's now showing "22".
2. Don't see any wifi networks. But access point is working and other devices can see me.
2.1 I found that wifi going to work then i tried to use gps. After few seconds phone starting see wifi networks and connecting. If turn off wifi and turn on again phone don't see networks and you need to repeat procedure.
3. Looks like gps not working too.. But tried only in indoor.
I can't understand is it software or hardware issue. Maybe seller changed imei number and model by firmware and did it wrong? Antutu showing strange imei.
Can i to know somehow real model of phone? I can try to make logs and attached it here. Or maybe somebode can check imei, bands with octopus box? I dont know what to do
P.S. Bluetooth is working. Tried to send file and it was fine.
I can't return phone to shop because im living in different country But phone is amazing! And I loved lg. I had lg optimus one (was lost and back by good people), then lg optimus black(was burned in bonfire), lg g2(left in taxi), lg g6 (was lost) and finally lg g7. Yeah, looks like something wrong with me or these lg.. But i love it
Did you put in your SIM card first before you started...
I read you need to insert sim first but could be wrong.
sas007 said:
Did you put in your SIM card first before you started...
I read you need to insert sim first but could be wrong.
Click to expand...
Click to collapse
Sure, i did it. Anyway don't search networks. But what carrier of sim card and numbers into sim card, phone can recognise.
Maybe i wrote not understandable? My english not first language. So asking. I will try to explain.
Thanks for your reply.
I uploaded a log file with errors but cant to write here link, because i need 10 messages
My G710ULM's GPS stopped working 2 days ago, still trying to find out what's the cause of it. Tried apps like GPS Status, GPS Locker, no avail that it isn't picking any satellites at all. Just searching for GPS location. Restarting the device haven't helped either. In settings I even excluded all apps in Power Saving Exclusions. In GPS Status app, resetted and downloaded the A-GPS, this should surely make the GPS work. No success.
deonin said:
Hello you guys!
I just received my lg g7 g710ulm. And when i turned on the phone i understood that im not lucky.. I need your helps! Please! Because i cant do it myself.
1. No signal. Don't search networks. Immediately getting error when trying to do it myself. "Preferred network mode" can't change due error and it showed "null". After reflashing it's now showing "22".
2. Don't see any wifi networks. But access point is working and other devices can see me.
2.1 I found that wifi going to work then i tried to use gps. After few seconds phone starting see wifi networks and connecting. If turn off wifi and turn on again phone don't see networks and you need to repeat procedure.
3. Looks like gps not working too.. But tried only in indoor.
I can't understand is it software or hardware issue. Maybe seller changed imei number and model by firmware and did it wrong? Antutu showing strange imei.
Can i to know somehow real model of phone? I can try to make logs and attached it here. Or maybe somebode can check imei, bands with octopus box? I dont know what to do
P.S. Bluetooth is working. Tried to send file and it was fine.
I can't return phone to shop because im living in different country But phone is amazing! And I loved lg. I had lg optimus one (was lost and back by good people), then lg optimus black(was burned in bonfire), lg g2(left in taxi), lg g6 (was lost) and finally lg g7. Yeah, looks like something wrong with me or these lg.. But i love it
Click to expand...
Click to collapse
I can fix it. Send me a PM.
Resolution?
Hi in having the same issues with my G7 thinq... I was wondering if you guys found a resolution for this issue?
5centr5 said:
I can fix it. Send me a PM.
Click to expand...
Click to collapse
Hello expert. I have an LG G7 ThinQ ULM phone. The problem of this phone is no phone waves signal, 3G, 4G. (a week ago that is good). I think that because the SIM and insert this SIM into other phones, this SIM still works very well. So can you show me how to fix it? Thank you very much!
Note: I was try as below but not success
Go to the Home screen;
Tap on the Phone app;
Switch to the Dial pad;
Type in (*#*#4636#*#*) and just wait – the phone should automatically redirect you to the Service mode;
Once you’ve entered this new mode, tap on Phone Information or Device Information;
Tap on Run Ping test;
Look for the button labeled as Turn Radio Off and select it;
Wait for the phone to restart;
Tap on reboot.
Problem on LG G710ULM OF WIFI, GPRS, SIM CARD READING
Hello i have the same problem on my LG G7 i buyed this motherboard but just problem again . please if you find a way to fix this. someone tell me how to do it :highfive:
hello i have the same problem. no wifi, no network.. enable radio in service menu not resolved problem... any solution??
Solution? I have the same problem
I can fix it with TV for little bucks.
got the same problem after trying to update
I've got the same problem after flashing the android 10 update. Tried android pie and oreo but nothing helped. I will really appreciate any help as this is my daily driver.
my imei wifi mac still exist and working but the problem still persist
update:
finally got my network working all you need is an original qcn backup or flash original modem_a,b partition with QFIL if imei shows null use this tutorial to change ur origin imei/MEID, im not gonna give full tutor or the file since no one answered me, good luck.
kunarbale said:
my imei wifi mac still exist and working but the problem still persist
update:
finally got my network working all you need is an original qcn backup or flash original modem_a,b partition with QFIL if imei shows null use this tutorial to change ur origin imei/MEID, im not gonna give full tutor or the file since no one answered me, good luck.
Click to expand...
Click to collapse
hi, i need help, same mistake, i dont get a solution
Hi guys, I bring a solution to this problem, I found this topic: https://forum.xda-developers.com/t/no-signal-after-crossflashing.4089281/, you understood better by reading yourselves, but basically I flashed the rom with lg up chip erase mode and my wifi/data started working again, I know this is not recommended under any circumstances but it worked for me.
However, be aware that ChipErase mode not only erases IMEI numbers, but also erases MAC addresses, EFS partition and others. In many countries if your device does not have an IMEI number or other identifiers, SIM networks cannot allow (my case in Brazil it worked) for you to register with them, i.e. in most cases your sim will not work on the phone and you will not have cell service. You may still have issues with WiFi networks as without MAC addresses your WiFi will be grayed out or the network may not allow you to connect. Also, be aware that in many countries around the world knowingly tampering with or changing your phone's IMEI numbers is against the law. IMEI number is how networks and ultimately law enforcement identify the device and its owner
kunarbale said:
my imei wifi mac still exist and working but the problem still persist
update:
finally got my network working all you need is an original qcn backup or flash original modem_a,b partition with QFIL if imei shows null use this tutorial to change ur origin imei/MEID, im not gonna give full tutor or the file since no one answered me, good luck.
Click to expand...
Click to collapse
hi can i use this method to fix my wifi problem? my wifi cant be turn on at all after so many change of roms, it does work on every firmware i used. i need a help
Related
I flashed CM10.1 on my S3 and had the same problem as others where data was intermittent. It worked for some time and after one nightly, I lost my IMEI. So I got back to stock, used the procedure with QPST and got back my IMEI. I got back to cm10.1 and unsurprisingly, I had a hard time having data. But worst off, I had a hard time having cell connection anymore, not even voice or sms. Tried AOKP without any luck. Tried different modems, not luck either. Now I went back to stock and still doesn't work. There's something that is not resetted between flash of ROM that keeps messing up my connection. I also found out that only one network provider is ever found, one is Rogers Wireless (I'm with Bell), or one is EXT. But never any other provider is ever found. And also in *#*#4636#*#* under phone info I can'T change the radio band like I can on the phone of my girlfriend.
So there it is. I'm stuck. I don't really want to buy another phone. It is a software issue for sure. But how can we solve that? Is there any way to restore the EFS to factory default? Could it be buried there? What is the ERI? Could it be that? My stock ROm says that it can't get the ERI version.
Any help is welcome.
my stock telus ERI is unavailable but i think thats normal... i have no problems
from what i understand imei and apn settings are the things to check into
24680 said:
my stock telus ERI is unavailable but i think thats normal... i have no problems
from what i understand imei and apn settings are the things to check into
Click to expand...
Click to collapse
IMEI and APN are good. IMEI will get me data, but I can't even get a cell connection now. No radio at all.
whats your radio band set to?
if i set mine to anything but automatic it wont find networks like yours..
*#*#4636#*#* dont work on my telus s3.
i use a different method
*#197328460# then
UMTS > Debug Screen > Phone control > Network Control > Band selection >
Automatic...
beware what you change in here as there is no return to default
24680 said:
whats your radio band set to?
if i set mine to anything but automatic it wont find networks like yours..
*#*#4636#*#* dont work on my telus s3.
i use a different method
*#197328460# then
UMTS > Debug Screen > Phone control > Network Control > Band selection >
Automatic...
beware what you change in here as there is no return to default
Click to expand...
Click to collapse
Neither of the two works. *#*#4636#*#* was working with CM10/10.1 and AOKP. But not with stock. And the one you suggest after is not working either.
But I remember going ot *#*#4636#*#* before flashing stock rom and I wasn't able to selet any band. On my girlfriend's android phone (HTC) I can.
if it were me.. i would try reflashing stock again... after flashing stock do a factory reset thru recovery... seems to help for clean stock setup.
if still no network i would check that band selection is set to automatic.
maybe someone else with more experience would have a better idea.
you mentioned you changed your band selection and now cant change it back.
i dont think flashing stock changes this.
i think that might be your problem.
ifso you first need to fix phone to use *# code... i have no idea why its not working
it works on my stock telus 4.0.4 and 4.1.1
maybe bell blocks from using *#code?
ebfortin said:
I flashed CM10.1 on my S3 and had the same problem as others where data was intermittent. It worked for some time and after one nightly, I lost my IMEI. So I got back to stock, used the procedure with QPST and got back my IMEI. I got back to cm10.1 and unsurprisingly, I had a hard time having data. But worst off, I had a hard time having cell connection anymore, not even voice or sms. Tried AOKP without any luck. Tried different modems, not luck either. Now I went back to stock and still doesn't work. There's something that is not resetted between flash of ROM that keeps messing up my connection. I also found out that only one network provider is ever found, one is Rogers Wireless (I'm with Bell), or one is EXT. But never any other provider is ever found. And also in *#*#4636#*#* under phone info I can'T change the radio band like I can on the phone of my girlfriend.
So there it is. I'm stuck. I don't really want to buy another phone. It is a software issue for sure. But how can we solve that? Is there any way to restore the EFS to factory default? Could it be buried there? What is the ERI? Could it be that? My stock ROm says that it can't get the ERI version.
Any help is welcome.
Click to expand...
Click to collapse
if i were u i would first try your girls sim in your phone and vise versa and if no luck do the qpst instructions to regain LTE not imei .and if u still cant manually find network operator after that i would format both sd cards and odin back to stock rooted and do the imei injection again for the hell of it and the LTE fix ..and stay on stock rooted or 4.1.2 until u get this figured out cause 4.2 builds are gonna have more probs then 4.1...I know u are having cell connect probs and these instructions are for imei and data but it sounds like your out of options....i lost imei once and had to manually inject with qpst and my reception was one bar til i did the LTE fix and it worked awesome..one more thing is my phone will not select a radio band ever unless i manually select my network operator first or i have no sim card in phone..i have also had sim cards crap out for no apparent reason..good luck
edit. my bad i thought your girl also had gs3..maybe the sims are still the same
stuey25 said:
if i were u i would first try your girls sim in your phone and vise versa and if no luck do the qpst instructions to regain LTE not imei .and if u still cant manually find network operator after that i would format both sd cards and odin back to stock rooted and do the imei injection again for the hell of it and the LTE fix ..and stay on stock rooted or 4.1.2 until u get this figured out cause 4.2 builds are gonna have more probs then 4.1...I know u are having cell connect probs and these instructions are for imei and data but it sounds like your out of options....i lost imei once and had to manually inject with qpst and my reception was one bar til i did the LTE fix and it worked awesome..one more thing is my phone will not select a radio band ever unless i manually select my network operator first or i have no sim card in phone..i have also had sim cards crap out for no apparent reason..good luck
edit. my bad i thought your girl also had gs3..maybe the sims are still the same
Click to expand...
Click to collapse
Thanks for your answer. Really appreciated. I've flashed so much time that I don't see the point of doing it again. I also had, at some point, to inject my IMEI and it worked with QPST.
What I find really strange is that a stock reflash doesn't put everything back to when I bought the phone. Funny thing, after the flash, it knew what my Wi-Fi router password was! So obviously there are some part of the config that is not overwritten. Which I find odd.
I also started playing with the service menu and found a lot of settings for the radio band. No luck yet.
ebfortin said:
Thanks for your answer. Really appreciated. I've flashed so much time that I don't see the point of doing it again. I also had, at some point, to inject my IMEI and it worked with QPST.
What I find really strange is that a stock reflash doesn't put everything back to when I bought the phone. Funny thing, after the flash, it knew what my Wi-Fi router password was! So obviously there are some part of the config that is not overwritten. Which I find odd.
I also started playing with the service menu and found a lot of settings for the radio band. No luck yet.
Click to expand...
Click to collapse
Your WiFi password could have been restored by google just like it puts your contact info back.
If you are doing a Odin to stock that should wipe it clean.
stuey25 said:
if i were u i would first try your girls sim in your phone and vise versa and if no luck do the qpst instructions to regain LTE not imei .and if u still cant manually find network operator after that i would format both sd cards and odin back to stock rooted and do the imei injection again for the hell of it and the LTE fix ..and stay on stock rooted or 4.1.2 until u get this figured out cause 4.2 builds are gonna have more probs then 4.1...I know u are having cell connect probs and these instructions are for imei and data but it sounds like your out of options....i lost imei once and had to manually inject with qpst and my reception was one bar til i did the LTE fix and it worked awesome..one more thing is my phone will not select a radio band ever unless i manually select my network operator first or i have no sim card in phone..i have also had sim cards crap out for no apparent reason..good luck
edit. my bad i thought your girl also had gs3..maybe the sims are still the same
Click to expand...
Click to collapse
This thing is so strange. There's only one network that my phone can see now, and it is 302720. Bell is 302610. No other network is visible. And since I'm with Bell, then I can't connect to 302720. I'm in for emergency calls only. That's why I thought it may have to do with radio. But it seems Rogers (302720) and Bell use the same bands. A channel maybe? But this should be all automatic! It's a pretty stupid bug let me tell you!
Maybe a SIM card issue? That would be quite a coincidence that it happen exactly when I'm playing with ROMs...
RUNNERX said:
Your WiFi password could have been restored by google just like it puts your contact info back.
If you are doing a Odin to stock that should wipe it clean.
Click to expand...
Click to collapse
Ah that's a good possibility. I didn't know it was saving passwords as well.
So if it wipes clean, how come this bug stays? There is obviously something that is not wiped and overwritten or else it would work.
How can one tell if someone losses their IMEI number? Unable to make phone calls? No 4g/ lte?
Sent from my SGH-I747 using xda app-developers app
Deggy said:
How can one tell if someone losses their IMEI number? Unable to make phone calls? No 4g/ lte?
Sent from my SGH-I747 using xda app-developers app
Click to expand...
Click to collapse
When you go to info about your phone, in status you usually have your IMEI number. It'll show 0 if it's corrupted. Or sometimes it's a generic IMEI dans is used when the real one is unknown. It's 049 something I think.
Without an IMEI number you can do phone call. But you'll never have a data connection.
Hi there
I am in New Zealand, recently rooted with DR Ketan’s help and installed PhilzCWM. Also on Ketan’s advice, I backed up my EFS.
My problem: just today I realised I cannot send text, or make phone call. I am on X-Note ROM from 3-4 days ago. I am very sure that after installation, I had normal Mobile connectivity and was surprised to find I didn't. Not sure if my EFS became corrupted, or other ROM setting is wrong.
Under Settings About Device:
My SERVICE STATE says Out of Service
My Mobile NETWORK STATE says disconnected.
My phone number says UNKNOWN
What's weird is
My IMEI lists a long number, assumed correct and not corrupted
So if my EFS partition is corrupted I assume I wouldn't see any IMEI at all?
Far as I know my SIM is activated (I am on a company plan & coworker's phones are normal)
Just now I restored my stock nandroid and .... same thing! No service. So I doubt it's even a modem problem.
Guys I'm screwed, any tips what settings to check etc??
sounds like your IMEI is invalid. i had something random recently. all my flatmates use iphone 4s. they had no signal when @ home. cant send texts etc. wifi works.
then next day my LTE N2 did the same thing. I changed MODEM/BASEBAND problem corrected it self. went back to old MODEM/Baseband. no problems since.
only other thing i can think of is, someone has reported your IMEI to police or your provider..
does it say "NOT REGISTERED" ? or something similar where your provider name appears?
R0B3RTF1SH3R said:
sounds like your IMEI is invalid. i had something random recently. all my flatmates use iphone 4s. they had no signal when @ home. cant send texts etc. wifi works.
then next day my LTE N2 did the same thing. I changed MODEM/BASEBAND problem corrected it self. went back to old MODEM/Baseband. no problems since.
only other thing i can think of is, someone has reported your IMEI to police or your provider..
does it say "NOT REGISTERED" ? or something similar where your provider name appears?
Click to expand...
Click to collapse
Hey thanks for th tip.
My phone recognises Vodafone as my provider but still won't connect.
I will try flashing a different modem, I may not have paid enough attention to different versions when I flashed the aroma installer.
Thanks, I'll report back.
update: Vodafone shop confirms my SIM is 100% good, and it works in another phone. So I think you're right, my IMEI is fukt.
I was told by Voda that my proper IMEi is listed on my phone innards. The IMEI shown in phone settings is waaay different. So it's corrupted somehow. I gotta familiarise myself with how to flash my backup image. Damn just what I need on beer day Friday
I restored my backup image of EFS/IMEI - it solved my problem.
Because there was an IMEI listed in phone settings I wrongly assumed it was the correct one. So flashing ROMS can muck up your EFS.....thank god for backups
you can still use the custom roms. just if your IMEI stuffs up, there is methods to reset it. i had to do it once. wasn't that difficult but was rather troublesome. i just wanted to use the custom rom at the time.
My phone started turning on and off its 3g connection. Wifi works solid.
I'm on a good signal area. It's not like the 3g is on and I can't connect in anything.
The problem is that the phone turns on and off. It doesnt fix the 3g connection.
Also, Checkin service it's draining the battery a lot.
Looks like a software problem with Google Play Services and its Connection checking service.
Anybody have seen this problem?
thanks in advance.
Starting to worry right now. Did a factory reset on a flashed V10j KDZ and it didn't change.
TWRPed a 20A Lollipop rooted ZIP and it didn't change. Right now I'm trying to go back stock using LG PC Suite.
I can't understand why this can be a hardware problem because 3G actually works but it keeps constantly getting on/off in ~10 seconds intervals.
Looks like a bad system file that is messing with it.
EDIT: Also, the phone can't search for mobile networks anymore. I just tell it to do a manual search and it can't find anything.
What would this be? Modem file broke? WTH.
alfablac said:
Starting to worry right now. Did a factory reset on a flashed V10j KDZ and it didn't change.
TWRPed a 20A Lollipop rooted ZIP and it didn't change. Right now I'm trying to go back stock using LG PC Suite.
I can't understand why this can be a hardware problem because 3G actually works but it keeps constantly getting on/off in ~10 seconds intervals.
Looks like a bad system file that is messing with it.
EDIT: Also, the phone can't search for mobile networks anymore. I just tell it to do a manual search and it can't find anything.
What would this be? Modem file broke? WTH.
Click to expand...
Click to collapse
I have random disconnects/drops too, Although my 3G/LTE icon never actually goes away, just the signal.
Personally I would suspect your modem as #1 suspect.
Factory reset rarely fixes much, I would try re-flashing the phone.
If KDZ flash doesn't fix it maybe try a tot & dll flash using LG Flash Tools with modified megalock.
It definitely looks like a modem issue BUT it can be a your os. I had issues where my modem wouldn't flash from a stock flash on my S4, But manually flashing my modem would SOMETIMES work, I would have to flash the modem a few times usually before it would actually flash.
I had problems before but it was caused by network. Did you tried with different SIM card from other network?
I have the same problem and couldn´t fix yet... Didn´t try to use another SIM card to check if is a network trouble, but it´s driving me crazy to be without connection and a huge battery draining...
Any other ideas?
viniciuscordeiro said:
I have the same problem and couldn´t fix yet... Didn´t try to use another SIM card to check if is a network trouble, but it´s driving me crazy to be without connection and a huge battery draining...
Any other ideas?
Click to expand...
Click to collapse
Just try with other network SIM. I had same problem long time back with Nokia n96, Motorola defy and some other phones. Some of time it helped to set phone only to use 2g network. That was happening the most of time when i used VIP network in Serbia.
Setting only 2g signal helped sometimes but after changing SIM card, problem was solved.
This problem happen to me without reason and after some time i tried same network again, there was no problems.
Probably a different SIM will correct the problem, because after a lot of trial and error changes I realized that the current Network APN (you can reach going on Mobile Networks inside Connections and Networks [translation] in the Settings) was faulty. I deleted the APNs and made a restore. (Delete and Restore are the only options inside Network APNs).
I imagine that changing SIM cards from another carrier will reconfigure the APNs and probably fix the problem.
I´ve tried a different SIM card and didn´t found any troubles, but when I put mine, the problem come back again... So it´s a problem with my carrier. I´ve deleted the APN settings, restart, restore, restart again and didn´t solve. I´ll call them to check if they are experiencing any network issues.
Hi everyone, good morning
I pose this problem ...
I updated my GT-N7100 from the stock version 4.4.2 to 7.1 RR, which is why the phone was no longer lit. The Samsung word appeared looping at its ignition and no reset options worked.
All after the battery suddenly abandoned me!
After the upgrade, unfortunately the mobile network is no longer detected, or rather, the phone does not hook up the signal even if mobile networks are detected (select networks, Vodafone, Tim, Wind, Tre).
If I try to hook my network manually (Tim), the error is the inability to record.
I checked IMEI and is present, and, as mentioned above, networks if you look manually are seen.
I've downgraded to version 4.2.2 to figure out if the problem was about rom, but even with this version the network is not hooked up.
I also tried with other sim, but nothing in fact.
Unfortunately the backup I made did not go well and did not save the files in the EFS folder .... the badge sees us well !!!!!
Do you have any suggestions?
I also tried to reflect the rom Viper, but no change in the network ...
What other tests could I do? Thank you all!
Hi guys,
I've got a Mi Max 64gb, it was working ok and then it auto updated to MIUI 9 and now i get no signal. If I go into setting, it will show my sim name (three) but thats it. It has no signal and I thus can not make or take calls. The status bar at the top says no service.
I purchased the phone second hand and everything was working fine so did a blacklist check just in case and both IMEI come back clear. Also when I switch from fin network automatically to manual, it will find a few networks but will no connect.
Anyone know what can be wrong? Phone has locked bootloader fyi.
waqas321 said:
Hi guys,
I've got a Mi Max 64gb, it was working ok and then it auto updated to MIUI 9 and now i get no signal. If I go into setting, it will show my sim name (three) but thats it. It has no signal and I thus can not make or take calls. The status bar at the top says no service.
I purchased the phone second hand and everything was working fine so did a blacklist check just in case and both IMEI come back clear. Also when I switch from fin network automatically to manual, it will find a few networks but will no connect.
Anyone know what can be wrong? Phone has locked bootloader fyi.
Click to expand...
Click to collapse
Anyone?
Ok so I got permission and unlocked the bootloader, installed TWRP and installed RESURRECTION REMIX 5.8.5 for hydrogen but its still showing no signal. Is there a way to check what can cause the problem as I've tried swapping sim trays (have a faulty one as spares).
Please show your holiday spirit and help me
waqas321 said:
Ok so I got permission and unlocked the bootloader, installed TWRP and installed RESURRECTION REMIX 5.8.5 for hydrogen but its still showing no signal. Is there a way to check what can cause the problem as I've tried swapping sim trays (have a faulty one as spares).
Please show your holiday spirit and help me
Click to expand...
Click to collapse
I really have no idea what your problem might be, but the panacea in all weird cases, irrespective of the particular symptoms, seems to be to fastboot flash a official global stable rom with the Miflash tool.
Then you have hopefully a base "known state" to start from.
If you still have no signal, you might well have a hardware problem.
cobben said:
I really have no idea what your problem might be, but the panacea in all weird cases, irrespective of the particular symptoms, seems to be to fastboot flash a official global stable rom with the Miflash tool.
Then you have hopefully a base "known state" to start from.
If you still have no signal, you might well have a hardware problem.
Click to expand...
Click to collapse
Hi Cobben,
Installed global stable rom, still having the same issue. Where do I go from here?
waqas321 said:
Hi Cobben,
Installed global stable rom, still having the same issue. Where do I go from here?
Click to expand...
Click to collapse
Hi,
I'm not any kind of expert at these kinds of (radio signal) problems today, though I do have a background in communications electronics construction (c.a. 1980's !)
If you did a complete format of everything before flashing the ROM, and it still doesn't work, I would guess you have a hardware problem.
Of course you want to double-check that your sim cards work in other phones.
I've had some rather weird problems caused by simcards.
You should even ask for a completely new simcard from some provider, and not put it into any other phone first.
How you could go about verifying that you truly have a hardware problem, without handing it over to a service center of some kind for testing, I really don't know.
Perhaps someone else has expertise in this area?
Otherwise, you just write it off as a loss, or sell it on Ebay for whatever you can get.
same with me. my phone not showing signal. the simcard is working before. it show no simcard after i flash twrp and supersu. the problem happen after restart phone. now i'm stuck searching this solution. help me.