If you are selling or giving away your Apple Watch, you'll need to remove the Activation Lock before someone else can begin to use it. This removes your Apple ID and other personal information ...
Apple has further consolidated resources on how to turn off Activation Lock on iPhone, iPad, or iPod touch on a new portal page linking to all support avenues that users can access.
Activation Lock is an anti-theft system for Apple devices meant to prevent unauthorized usage or erasure. It's available on most Apple products, such as iPhones, iPads, Macs, and Apple Watches.