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First off; they're not part of Aternos whatsoever.
My guess is that your friend decided to try and troll you, because they can't just get access to your server out of nowhere.
Maybe my girlfriend was getting bored and wanted to troll me. Thanks for the answer anyway 
I was playing on a server (mine) and two unknown players came in (Iunderstand and AternosStaff). I understand that he had an OP and no one gave it to him. None of my friends who might have an IP are good at English, nor do they have friends from English-speaking countries. Getting down to business, the players started destroying mine world and I couldn't ban them because they unbanned right away. I just shut down the server and I am terrified and confused. Someone like that? I am counting on help. 
(sorry for bad english im from Poland) Edit: I skipped the moment of talking to players, if I have to, I will publish it in this post.
