IPHONE CALL CLITCH

Ugh! I’m so annoyed, lately I’ve been having lots of trouble with my phone calls. I have a iPhone 11 and it works great except for calls it always hangs up after a couple of hours I’ve never made it past a four hour call! This is extremely frustrating for me and my boyfriend because we like falling asleep on the phone together and it’s sad when we both wake up in the morning to see how long we’ve been on the phone and it says call failed or ended! Does anyone else have this problem? Also yes I’ve reset my phone and updated it blah blah blah…