Watch11 passcode

Did you already force restart your watch by holding the Digital Crown and the Side button together for about 10sec, until the Apple logo comes back again?

If your Apple Watch passcode is still not working after a restart, you will have to reset the watch as explained in this related article:

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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 the power button in the upper-right corner of the display.
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.

Erasing all content and settings erases all media, data, and settings from your Apple Watch, but it does not remove Activation Lock. To remove Activation Lock, unpair the watch first. Before your watch is erased, a backup of its contents is created on your iPhone.

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How to reset your Apple Watch using your paired iPhone

1. Keep your Apple Watch and iPhone close together until you complete these steps.
2. Open the Apple Watch app on your iPhone, then tap the My Watch tab.
3. Tap General, then tap Reset.
4. Tap Erase Apple Watch Content and Settings, then tap it again at the bottom of the screen to confirm. You might need to enter your Apple Account password.
5. For Apple Watch models with GPS + Cellular, choose to keep or remove your cellular plan:

• • If you want to pair your Apple Watch and iPhone again, keep your plan.
  • If you don't want to pair your Apple Watch and iPhone again, remove your plan. If you aren't going to pair with a different watch or iPhone, you might need to contact your carrier to cancel your cellular subscription.

6 . Wait for the process to finish, then set up your Apple Watch again. When asked, restore from a backup.

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copied from: If you forgot your Apple Watch passcode - Apple Support