Why is my iPhone not detecting my SIM card?
my sim card stopped working even though it worked hours ago , it says sos
[Re-Titled by Moderator]
iPhone 12, iOS 17
Question marked as
Did you already force restart your iPhone?
Force restart iPhone - Apple Support
Also have a look at the troubleshooting mentioned in this article:
If you see No Service, Searching, or SOS on your iPhone or iPad - Apple Support