Phone on iPhone XR

I've been having a lot of glitches with the phone app, even after manually resetting my iPhone XR that I purchased in April 2019. Whenever I click the phone app button, once I am in the app, it doesn't allow me to click on anything. I can't go to the key pad, voicemails, favorites, and I can't even call anyone that is on the recent option. Even after closing out of the app and refreshing it doesn't allow me to. This occurs 80% of the time I try using the phone app, the other 20% it works, but it's frustrating because I never know when it will actually work. sos