i have forgotten my password to update my watch

How to reset your Apple Watch if you forgot your passcode

1. Put your watch on its charger and keep it there until you complete these steps.
2. Press and hold the side button until you see Power Off.
3. Press and hold the Digital Crown until you see Erase all content and settings.
4. Tap Reset, then tap Reset again to confirm.
5. Wait for the process to finish, then set up your Apple Watch again. When asked, restore from a backup.

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If you forgot your Apple Watch passcode - Apple Support