What is it says “example@gmail.com” cannot be used to unlock this Apple Watch
My uncle gave me a watch and it says my Apple ID can’t use a Apple Watch
Question marked as
Activation Lock is designed to prevent anyone else from using an Apple Watch if it's ever lost or stolen.
About Activation Lock on your Apple Watch - Apple Support
Activation Lock is an anti-theft feature that cannot be bypassed. Only the previous owner can remove the lock by using their Apple ID & password. Apple will not help you find the previous owner. If the previous owner cannot or will not remove the lock, then the watch is useless to you or anyone else. Dispose of the watch properly.
If you are the ORIGINAL owner, then see the 'Start a support request' section in:
How to remove Activation Lock - Apple Support