Do this first
Put it in Lost Mode now
- If your Apple Watch goes missing, you can immediately lock it using Lost Mode from your paired iPhone or iCloud.com/find.
- On your device
- Open Find My, tap Devices, then select your Apple Watch.
- Tap the More button next to your watch's name.
- Under Lost Apple Watch, tap Lost Mode.
- Tap Continue.
- Enter a phone number where you can be reached, then tap Next.
- Enter a message that you want to show on the watch screen, then tap Next.
- Tap Activate.
- On the web
- Sign in to iCloud.com/find with your Apple Account.
- In the Devices menu, select your Apple Watch.
- Select Lost Watch.
- If your device is offline, the contact information you entered for Lost Mode will appear when your Apple Watch is back online.