Unable to activate iPhone 7 in an older IOS
My dad has an A1660 iPhone 7 and he has been using the phone for a few years. Few weeks ago, the phone was black out. After we have reset the phone, the phone is still stuck in the screen of unable to activate, an update is required to active your iPhone. I tried to restore and update the IOS from the PC computer, but It wasn't successful. We're pretty sure the SIM card was working because we swapped the SIM card to a different iPhone with no problem. Does anybody has the same experience? What is your solution?
iPhone 7