Some T-Mobile branded iPhones are suffering from blue screens and random restarts
Some T-Mobile branded iPhones are experiencing a blue screen before restarting
One person affected by the issue was able to end it by disabling Wi-Fi calling. If you want to try that before a factory reset, go right ahead. Trying to find a cure without having to go through that headache seems like it would be a goal to aim for.
"Hey guys. So this morning my iPhone 6 (4 months old) started just randomly restarting itself every 20-30 minutes or so. I wasn't even using it most of the time, it was in my pocket at work (could tell because of lock screen that indicated I needed to enter my pin after a restart as opposed to finger ID). At one point I was texting my SO about it, the screen turned blue for maybe 2 seconds and it restarted."-Anonymous T-Mobile iPhone user
source: MacRumors
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