Apple Watch shows activation lock

The person that you bought/got this watch from needs to follow all the steps in this link;

Remove the Activation Lock so that the buyer can use it.

If they can't or won't then get your money back or recycle the watch and mark it down as a bad experience.

If you cannot contact them, then the device is useless to you. Only the owner that put the lock on the device can remove it. See if there is a way for you to remove it, or report it to this company to see about a refund.

The fact that they won't respond to you is a good indicator that the watch you bought is stolen.

Turn it over to the police.