If you forget your Apple Watch passcode
If your Apple Watch is disabled because you forgot your passcode or entered an incorrect passcode too many times, you can use the Apple Watch app on your iPhone to allow you to enter the passcode again. If you still can’t remember your passcode, you can reset Apple Watch, reset the passcode, then restore Apple Watch from a backup. Restoring erases the content and settings on your Apple Watch, but uses a backup to replace your data and settings.
Important: If Erase Data is turned on, the data on your Apple Watch is erased after 10 failed passcode attempts.