Apple phone touch screen not working

I have an Apple ?3 operating with the most recent updates. Yesterday the watch face started suddenly blinking At rest. The battery is charged, I Unsuccessfully tried to put my passcode in but kept it on during my workout. Suddenly, it prompted me to record my workout and started blinking again after I was finished. The battery is charged, I shut it completely down, I unpaired it from my phone and have been unsuccessful pairing it again. Anybody experienced this? Any repair ideas?? Thank you in advance for any ideas.