Apple watch icloud lock

I bought an apple watch series 4 with broken screen online, after having the screen repaired, I started to configure the watch with the phone, after a few steps I was asked for the e-mail and password of the icloud of the owner of the watch. I tried to contact him but he blocked my number so I can't even contact him anymore. now i have a repaired apple watch but i can't use it anyway. can you tell me a solution?