Device: iPhone 8 with iOS 12.2 (MQ62LL/A)
I live in downtown San Francisco where LTE service should be more than ample according to coverage maps. Since switching to T-Mobile, I've experienced great LTE service 90% of the time but sometimes my phone will switch down to Edge mobile data randomly. I know it's not a poor coverage area because it has happened near my office and home where service is usually pretty good. Sometimes it will switch back to LTE if I go into Settings > Cellular > Cellular Data Options > Enable LTE and turn LTE off then back on, and then restart the phone. But this is a long and painful process especially if you're standing in line somewhere trying to use your phone to complete a purchase, pull up an email, etc.
Anyone have any tips? Getting so frustrated I may switch back to Verizon which would cause me great pain I've tried contacting my team of experts but they haven't been able to resolve the problem. They opened network trouble ticket to see if there was an outage in my area but didn't find anything.
This does sound hardware specific the way you describe it. I would try doing a full NW reset on the phone and if that does not work, we can see about replacing your SIM card.
To reset the NW settings, tap Settings > General > Reset > Reset Network Settings. Please know this also resets Wi-Fi networks and passwords, cellular settings, and VPN and APN settings that you've used before.
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