How to reset my Apple Watch after buying second hand?

Hi

You are describing Activation Lock, which prevents unauthorised use of Apple Watch if it is lost or stolen.

To be able to pair the watch to your own iPhone, you would need the previous owner (who may not be the seller) to either enter their Apple ID and password on your iPhone or to turn the feature off via https://www.icloud.com/ by signing in with their Apple ID > Settings > My Devices > Click on Apple Watch > Click on the "X" > click on Remove.

If you cannot arrange for the previous owner to do this, you should return the watch for a refund.

You will not otherwise be able to use the watch.

There is no way around this security feature.

If you purchased the watch via a website such as eBay, it was misdescribed by the seller and the seller cannot be reached or will not remove the lock, consider lodging a claim (eg under the eBay Money Back Guarantee).

More information:

About Activation Lock on your Apple Watch - Apple Support

Your watch may have an activation lock. See this support article: About Activation Lock on your Apple Watch - Apple Support

The previous owner needs to unpair the watch from the iPhone it is paired with.

Turn off Activation Lock before you send your Apple Watch in for service, sell it, or give it away

Before you send your Apple Watch in for service, sell it, or give it away, you should turn off Activation Lock on your Apple Watch. Just unpair your Apple Watch from your iPhone:

1. Keep your Apple Watch and iPhone close together.
2. Open the Apple Watch app on your iPhone and tap the My Watch tab.
3. Tap your watch name at the top of the screen, then tap .
4. Tap Unpair Apple Watch.
5. Enter your Apple ID password. If you forgot your Apple ID password, you can reset it.
6. Tap again to confirm.

If you can't access your iPhone or Apple Watch, or if your Apple Watch isn't paired with your iPhone and you need to turn off Activation Lock:

1. On a computer, go to iCloud.com and sign in with your Apple ID.
2. Go to Find My iPhone.
3. Select All Devices, then click your Apple Watch.
4. Click Erase Apple Watch. Select Next until the device is erased.
5. Click next to your Apple Watch.