Apple Watch face is sometimes blackened
why does the face of my Apple Watch turn black and doesn’t respond to my taps… then later it lights up again for no reason
Apple Watch Series 8, watchOS 11
Have you tried a force restart?
Press and hold both the side button and Digital Crown until the screen turns black and the Apple logo reappears, then release both buttons. Your watch may take a few moments to restart.
Never do this when updating watchOS!