Touchscreen works poorly on iPhone X

My iPhone X is less than 6 months old. The touchscreen doesn’t work well. It is not totally unresponsive. Howeve, I often have trouble with it not responding. This happens in a variety of screens and apps. Normally I can close that screen and reopen i, then it works. However, that seems like something that I should not need to do. Is there a fix for this, or is it a warranty problem requiring replacement?