iPhone 6s stuck on charging screen
I have an AT&T refurbished 16GB iPhone 6s. Within the past month it's been shutting down out of nowhere without being dead. Sometimes it'll say it's dead when I power it back on, then a minute later I try again and it's fine. This happens around 4 times every day. The only reliable way I've found to keep it from shutting down is to keep it plugged in at all times and I cant always do that. The Maximum Capacity the battery was at (in settings> battery> battery health) 79% when I checked today. It's running the latest iOS, 11.3. It shut down about 20 minutes ago on an 80% charge. I plugged it in right away. It's been saying its charging with the empty battery picture on the screen since and it won't go past that:
Should I call AT&T for a replacement on my insurance or is there a method to power it back on? Sorry it took a while to say that but if anyone can help with the other problems I listed I would be very thankful.
iPhone 6s, iOS 11.0.3, 16GB
