So if you were a CT and some CT's told you to go through vents and kill everyone in a briefing it would be ARDM RDM or MRDM and that results in a 2 week ban. This is may be the case. In future never listen to some random CT's and in events only listen to the event planner.
Also like That1RussianDude said edit your SteamID into the unban request.