My sister’s ex boyfriend blocked her and me on all social media platforms?

My sister and her boyfriend broke up about 6 months ago, he was really close to the family he has all of our cousins on his social media and we all follow him. Yesterday all of the sudden he blocked me and her on all platforms! Facebook, instagram, whatsapp, you name it. After they broke up he would still sometimes like my posts on facebook and like all of my posts on IG and he was one of the first people to see my stories on IG, he never missed one. All of that till yesterday he suddenly blocked me and her. But he is still following our cousins. And he is still friends with our guy cousin (they were friends even before him and my sister got in a relationship). So i’m really wondering why the heck would he do that! It’s already weird if you block your ex after 6 months of breaking up, but why her sister? What have i done?
My sister’s ex boyfriend blocked her and me on all social media platforms?
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