How to solve? iCloud lock to owner

Activation Lock is designed to prevent anyone else from using a device 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 device is useless to you or anyone else. Try to get a refund (through eBay) or dispose of the device properly.

If you are the ORIGINAL owner, then see the 'Start a support request' section in:

How to remove Activation Lock - Apple Support

In order to unlock Activation Lock, you will need the Apple ID and Password of the original owner who set up the device. Without that info, you will not be able to use the device. We cannot help and Apple will not unless you can produce the original receipt clearly showing the serial number. All of this is a theft prevention feature.

How to remove Activation Lock - Apple Support