How do I bypass activation lock on a series 3 Apple Watch

To remove the activation lock you can either remove it with the correct Apple id and password

Or if you are unable to do so, and you have proof of purchase, you can apply for Apple to remove the activation lock

See this guide:

How to remove Activation Lock - Apple Support

The step to remove without knowing the Apple ID is under Start a support request

then "Get started" on the next page

Here is the direct link:

https://al-support.apple.com/#/additional-support

Good luck!