Finding previous owner

Unless the original is willing/able to unlock that watch for you, you will not be able to use that watch. They should have gone thru these steps:

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

The link also provides this good info. Going back to the seller was good advice. See if you can get a refund on that watch? Unfortunately Apple Support will NOT help you find the original owner.

Before you buy a watch from a third party

Before you buy an Apple Watch from someone other than Apple or an authorized Apple reseller, make sure that the device is no longer linked to the previous owner’s account.

1. Identify the model of Apple Watch. 
2. Make sure that the previous owner removed Activation Lock from the watch and that the watch has been erased. They must unpair the watch and remove Activation Lock by entering their Apple Account password, so you can use the watch. 

• • If you see the passcode lock screen or the Home screen, the device needs to be erased. 
  • If you can, try to pair the watch with your iPhone. If you're asked to enter the previous owner's Apple Account password during setup, then Activation Lock is still on.

1. For cellular models of Apple Watch, make sure that the previous owner removed and cancelled any active cellular plans.

khaylon wrote:

Hey I bought an Apple Watch and it was locked. How is it possible for me to find the owner or any information with the serial number

It's not. Return it and get your money back.

If the seller won't refund your money, turn it over to the police. There is a very strong possibility that it's stolen.

Contact the person you bought it from. Aside from this, you can't.

(265354)

First contact the owner. If not happening then go to the place from where you bought the Apple Watch or contact apple support.

Best of luck

JayVachhani15_cool