Yesterday I went to the server and received a message about the ban, before that I did not play for 5 days. I didn't use any cheats or hacks. I cant understand reason why i'm banned. Please help me.

You got banned for a Punkbuster violation. Create a support ticket at Evenbalance here: http://evenbalance.com/support.php

If Evenbalance admits the violation has been triggered by mistake, we will remove the ban.

For now:

APPEAL DENIED