How to remove activation lock on Apple Watch

If you bought a used Apple Watch, only the owner who locked the watch can remove Activation Lock. Without their assistance, the watch is useless to you. Apple will not unlock it for you unless you are the original owner and you can present the original purchase receipt to Apple, which clearly shows the serial number on it.

If you are the original owner and you just can't remember your Apple ID and Password, see this --> About Activation Lock on your Apple Watch - Apple Support