Dropped calls

[IFTARP]

I have two different model iPhones and both are dropping calls when they did not before.  How has where I lived become a dead spot.  They work away from my neighborhood.  I use my phone for work, never had a problem and now our phones dont work

[CTGalloway21]

I bet it is because they forced HD Calling on and gives us no way to turn it off.  That's why my phone is dropping calls.