Chosen Solution

My iPhone 6 has gotten water damaged, the SIM indicator is red. It stopped working for a while, and now it is restarting randomly. Any suggestions?

Edit after replacing battery. So, even after replacing the battery, it is still restarting randomly, not as fast as before, but coconutBattery is still showing 5.5% Battery Health even after replacement. Could this now be a chip issue?

Battery has gone bad. I recommend getting the phone inspected for liquid damage. If none got on the board and screen still looks fine then you might just be able to get away with just a battery replacement.

Dude, H2O and cellphone or ANY electronic device don’t do well together. Lesson learned, and get another phone.