Apple Watch Activation lock

Activation Lock is designed to prevent anyone else from using an Apple Watch if it's ever lost or stolen.

About Activation Lock on your Apple Watch - Apple Support

Activation Lock is an anti-theft feature that cannot be bypassed. Only the previous owner can remove the lock by using their Apple ID & password. Apple will not help you find the previous owner. If the previous owner cannot or will not remove the lock, then the watch is useless to you or anyone else. Try to get a refund (through eBay) or dispose of the watch properly. In the future, see the 'Before you buy a watch from a third-party' section in:

What to do before you sell, give away, or trade in your Apple Watch, or buy one from someone else - Apple Support

Also see:

The All Too Common SAD Reality of Buying … - Apple Community

Palomiiino wrote:

The apple watch that I bought off of facebook marketplace has an activation lock on it and I can't contact the original owner please help

You got scammed. Recycle it. Yes, really. Recycle. The seller is gone, Facebook is, well, Facebook, and Apple won’t help without proof of ownership you don’t have. So… recycle it.

Th following tip references iPhone and iPad, but applies equally to Watch:

… The All Too Common SAD Reality of Buying a used iPad/iPhone - Apple Community