Banned but not ban listed

My girlfriend is an old player of this server. She played using nickname Zelda, and yesterday, when she tried to connect, she receive this message : "Disconnected / STEAM_1:0:677526873 is banned". Is very strange because i can not find her name / steamID on the the ban list. The is banned but is not ban listed. That means I can not say anything about ban reason. That reason is not listed anywhere. Can somebody check this problem ? Thank you

I assume it was on alServ1014?
This happens sometimes on L4D.
The SteamID is banned only on that server then and it is not visible in SourceBans.
I've remove the bans via console (listid and removeid).
9 different IDs were banned that way.
Should work now again.
Oh, and next time please add the server name to your request.

Thank you very much