If you tried to mute him under the players tab, and selected mute player from the drop down menu, then he isn't muted.  If you copied his, name, ip, and hash then pasted it under the muted players tab then it would show up and he would be muted.  Depending on what u did he may or may not be muted at all.    That fucknut X_Z$e$v$k_X was someone I muted....he really really needed to be.