Apple watch
My Apple Will not allow me to input code to unlock. Does not hold the code
Apple Watch Series 6, watchOS 9
Question marked as
First force restart i.e. press and hold both the side button and Digital Crown for at least 10 seconds, then release both buttons when you see the Apple logo.
If that doesnt help you will have the follow the steps in this article
If you forgot your Apple Watch passcode - Apple Support