Big baby butt

[LIB]

Ok this guy ''BIG BABY BUTT'', just piss off everybody on the CSS Gungame server, mostly the admins like me or any other admin. The problem is that we can't find him in the ban list or in any other list (mute,slay,kick,etc.). He knows that, so it's like he is hacking the server or something. LITTLE BABY BUTT and BABY ADULT BUTT do the same thing too, and they are not on the lists too. If a major admin can ban them by Steam ID, it would be more than appreciate.
Thanks,

I have the ID of BABY ADULT BUTT but only him, dont have for the others.
# 852 "BIG ADULT BUTT" STEAM_0:1:23390944 03:30 103 0 active