sim card not installed and phone heats up
I started to repeatedly get the message "sim card not installed' on my iphone since yesterday. I switched to airplane mode and then on again a few times to get the service back, but now when I do that, the phone starts to heat up. Is this problem a SIM card/service provider problem or is it an iPhone (iphone 13 pro max) problem? My iphone is newly bought.
iPhone 13 Pro Max, iOS 15