SOS stuck on iPhone 13 after upgrade to IOS16
I upgraded to IOS16 on Sunday. On Monday, I got a message 'SIM not available' and the phone went into SOS mode. I looked up how to stop it and had no success with the Volume Up, Volume Down then turn off as my phone would not turn off by just holding down side button. I turned off the phone and let it charge for a couple of hours and the SOS went away. Today, I was texting when suddenly 'SIM not available' came up again. Charging the phone has not fixed the problem. (While texting I was NOT hitting the volume buttons or the side button.) I cannot use my phone. Please HELP!