Touch Screen of Lower part of iPhone XR not working

Last few days the touch screen of the lower part of my iPhone is behaving irregular. I reset the phone to solve. I found that it's working. Again after 2 days the same problem revived. This time I reset with option of deleting all the data and apps. After that I was trying to reset my phone manually. Again I find that the lower part where the command button "Set manually" written is not working with touch of my finger. So I could not reset my phone yet. Can anybody help me to overcome this issue?