How should I solve my cellular issue

Check your iPhone settings

Go to Settings and turn on Airplane Mode, wait five seconds, then turn it off. Check Do Not Disturb. Go to Settings > Focus > Do Not Disturb and make sure it's turned off. Check for any blocked phone numbers.

If you can't make or receive calls on your iPhone - Apple Support

Hey,

I had this issue as well. Do you use an eSIM?

After contacting my carrier, they had me try it with the physical SIM instead—if you don't have one, order one from your carrier. Try it with a physical SIM. Though Apple had said it was a hardware issue, my carrier concluded it was the eSIM (embedded SIM) in the phone that had broken. Unfortunately, I must keep it on the physical SIM, but this solution restored service to me and helped me avoid a pricey repair.

iPhone 7 I’m not call and tex massage