can't call another iPhone on att network

You say it won’t call another iPhone on a specific network…doesn’t clearly say you can’t make calls at all. Is this the case?

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

Is this a new phone or did the phone work initially and now suddenly won’t? If you try everything in the link I provided then your next step will be to call AT&T on the other iphone you mentioned or another phone…or physically go to your local AT&T store for assistance v

Contact ATT

Soooooooo use a friend or family members phone. Or go to an AT&T store.

Cannot call sooooooooooooooooooooooo!!