How can I unpair my watch from a broken phone

On a computer, go to iCloud.com and sign in with your Apple ID.

Go to Find Iphone.

Select All Devices, then click your Apple Watch.

Click Erase Apple Watch.

Select Next until the device is erased.

Click the remove button next to your Apple Watch.

Try this :)

Factory reset directly on Apple Watch

1. Open the Settings app on your Apple Watch.
2. Tap General.
3. Swipe down to the bottom and tap Reset.
4. Tap Erase All Content and Settings.
5. If you're using a passcode, enter it when prompted.
6. Swipe down and tap Erase All or Erase All & Keep Plan if you have a cellular watch.

You can't pair 1 watch with 2 phones

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