Why was I banned?

Hey, let me start off by saying this is not a plea for help, nor asking for mercy, because I already had a 20 min queue dodge timer for leaving games. Although I have no ban history, I imagine whatever rule I broke to get instantly permabanned must have been a harsh one, so could someone at riot tell me what I did wrong? The email address associated with my account was not verified at the time, and I opened a support ticket last night just asking what I was banned for and no reply yet. Just want to make sure I know what I did wrong so I know not to repeat the offense again on my next account. Thanks!