About security in UNITY

Hello there =D
excuse me for the wrong english, I speak spanish jejeje

I have a question about this great software
can I restrict some final proyect made for web player???

This file is in some server of a costumer, the customer not pay an I want cancel this file,
but i dont have access to server to delete this file, and they are using mi proyect without contract =/

can I restrict my proyect whit some tool or any option???

Thanks for all and…Saludos compañeros expertos en UNITY !!!

There is no such option or tool.

Relaunch the game with a new version that creates limits for re-purchase and get people to sign in for free except the bone-head.