CS:GO Account Banned for No Reason After Facebook Login

I set up the Counter Strike game, played a few practice rounds, and was then presented with two choices: a Facebook login or a standard guest account. I decided to go with Facebook. I had a previous account that was already at level 2. Upon logging in, I was banned without any action on my part. Following that, I was unable to reach the game. The warning message indicated that the user has been banned from the game for using unauthorized software or displaying negative behavior that goes against the community guidelines. I didn't do anything; I hadn't even finished playing the game. Could you please reinstate my account?