Unable to make or receive calls iPhone 7 Plus (iOS 15.7.2)

[LDNW10]

This is an ongoing (random) issue with a iPhone 7 Plus.

I talked to Apple today and they are saying its a carrier issue so I'm trying to figure out if this is the case. But before I call BT support I'm checking here to see if anyone has had the same issues:

1. The hardware has passed the Apple in-store tests.
2. A fresh iOS has been reinstalled (not from a backup), version 15.7.2
3. To make calls I have to shut the iPhone down and restart which allows me to make one or two calls
4. Occasionally I can receive calls but often the phone will ring but without displaying a button to pick up
5. The camera is slow and often cannot focus
6. All other apps work as expected (minimal apps installed after reinstall)

Any help on this would be appreciated.

[countrypaul]

Sounds like you have been to an Apple store to get the phone checked. If you can do so easily, see if you can go back and try your Sim in a different handset (same model) and see whether that works properly or not as it souds more like a handset issue.

Sorry was thinking this was a new phone.  Might have to see if someone with the same model handset can help.

[stevebrass]

yep. Try the sim in another phone. And/or get a cheap sim and try that in your phone.