Touch screen becomes unresponsive.

I wonder if anyone has seen this problem before. I have an iPhone 7 Plus and have a problem that has been going on for a couple of years.

A few times a day my screen will become unresponsive to touch. I can quickly correct the problem by tapping the sleep/wake button, which of course requires me to re-enter my password, and then the touchscreen works normally. Another method I can use to correct the unresponse touch is that I can rotate the screen, forcing it to go into landscape mode, and then rotate back and then the touchscreen works normally. Note that neither of these methods requires restarting/resetting the device. Over the time I have had this problem I have rebooted the device (both hard and soft) and reset/restored the device multiple times and behavior remains the same.

Any thoughts?