How to stop my brother from being a cockblock?

I have asked my brother more to stop being a cockblock. But he won't listen. He picks my lock on my door. I've even put a sock on the doorknob but he takes it off. He has opened my bedroom window from the outside, I've even paid him to not cockblock but it's still not helping. My girlfriend is starting to get pissed. We have had sex at her house, but winger we try to have sex at my hous my brother is cockblock 80% of the time. Why is he cockblocking so much?
How to stop my brother from being a cockblock?
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