Can't unban my friend

Hello,

So, after I banned my friend at Aternos server site, I can't unban him!

I've tried to delete him from banned players, he deletes after I click on trash can, but after I go back to that page, he is still here! And, I can't /pardon him from command console - "That player is actually unbanned".

I need help asap, because we want to play now.

Sincerely,

Alex.

P.S. I don't use plugns on my server.

Nevermind, I've just closed the server, and it helped.