iPhone XR is dropping my calls too...

As I'm reading all the troubles good people are having with dropped calls on their XR, I can attest to the fact that it's happening to me also. As a teacher working remotely, I contact a number of parents via my iPhone XR. Each time I contact a parent my call gets dropped over and over again. Disgracefully so, I start my conversations by sayin, "please forgive me but our call will be dropped at anytime, don't worry I'll call you back". Some parents understand and others feel bad for me. I have an Apple case number that I'm constantly working with a tech representative. My iPhone has gone through several diagnostics to no avail. My iPhone XR was replaced by another iPhone XR, same results. I changed carriers, no difference. I reset the iPhone and installed all my contents from scratch, no difference. Everything works fine except the dropped calls. I'm glad I have a landline because my iPhone XR is undependable. Just today, I experienced 3 dropped calls. By the way, my troubles began with the installation of IOS 14. Apple, please take a good look at your IOS 14 vs the iPhone XR architecture, something is not adding up. Thanks,

Disgruntled and disappointed!