ot sure if this is the correct place for this question, but if not, I'm sure the powers that be will swiftly move it to a correct forum.
I updated my Factory Unlocked Samsung Galaxy+5G, connected to T-mobile the other day. Understand, I'm in the process of determining if I want to upgrade to the S21 Ultra, or the iPHone 12 Pro Max, so I've been switching the SIM back and forth between the two phones. I've not had any sort of problem until this latest thing.
Yesterday, I tried to use the Galaxy away from my home network, and it said that there was no internet connection. I immediately thought that I had forgot to switch the SIM, so when I got home, I checked, and the SIM was in the Galaxy. I switched the SIM to the iPhone, (11 Pro), and it's working fine. Switched back to the Galaxy, and it refused to connect to the T-mobile network. I cleared the cache via the internal recovery menu, and tried again. Still the phone wouldn't recognize the T-mobile network. Checking in the data connections, it shows that the access point is with T-mobile, and all of the APN data is there, and correct, however it's grayed out.
I contacted T-mobile, and they walked me through a few things, none of which were successful. I later decided to do a full reset via the Recovery menu, and after rebooting, I still see that T-mobile is the carrier of choice, except it simply won't connect, it tries, and goes through "trying to connect" for about 5 minutes, and then says that it can't connect. I am wondering did I kill this phone when I upgraded via the internal Samsung menu to Android 11, and OneUI 3.0? Has anyone else seen this? PLEASE, help me, as this little issue is really going to affect my choice as to which phone to upgrade.
Update on the above situation. I had an old Verizon SIM that I put in the phone, (Galaxy S20+), and it recognized it, could call the #611, and got an automated attendant. Noticed that the Verizon label was at the top, indicating that it was on that network, as did the Access point information. I removed the Verizon SIM, replaced it with the T-mobile SIM, nad I had T-mobile network, full, and complete connection. I knew I would have to reenter all of the passwords, etc, so I removed the sim from the Galaxy, and put it in the iPhone, and went to bed for the evening.
This morning, I swapped the T-mobile chip from the iPhone and put it back into the Galaxy S20+, (remember, this is the Android 11/OneUI 3.0) and it wouldn't connect unless I had the WiFi turned on. I'm beginning to think this might be a hardware problem, anyone else? I would sure like to have other opinions on this, hopefully someone reads this thread.