iphone 12 loses celluar connectin but has bars

Hi my iPhone 12 randomly loses cellular connection but I still have bars. I’m on bell and it’s not bell because it works flawlessly on my pixel and iPhone SE. so what’s happening is at random I am not able to load anything (google, apps, exe.) I try everything like restarting the phone but no luck. The things I tried are

network reset

full reset

converting the physical sim to e sim

reloading the e sim

restarting the phone

updating the os (it’s been a issue since iOS 16)

I’ve even took it to the apple store and they couldn’t find anything wrong and said the phone is in good health asides from the battery which is at 81% health.

I’m completely lost and I’m done with this issue.