My iPhone will not charge
It’s plugged into charger but won’t charge
Perform a Forced Restart on the phone. Follow the instructions very carefully, as this is a bit tricky. You may need to repeat this several times.
Force restart iPhone - Apple Support
There are only 2 possible results when you perform a Forced Restart:
1) The phone returns to normal operation
or.....
2) There is a hardware problem with the phone that will need attention at the Apple Store (make an appointment) or at an authorized Apple Service shop