I might get perma banned for breaking a rule I didn't know existed

Four days ago I challenged one of my friends to a friendly 1v1, I am significantly better than them so the outcome of the game was essentially decided when they agreed to face me. I didn’t want them to think I was going easy on them so I banned my friends most played champions, they are a support player so I banned Nami, Lulu, and Janna. After the match, which I easily won, my friend sent in a support ticket to Riot and told me my account would be banned within the week. I was shocked and my friend told me it was against the ToS to ban all support champions against a girl. After some research I found it to be true even in LCS that banning all support champions against females is not allowed, even if there is no evidence of it being malicious or showing disrespect. I enjoyed playing League of Legends for the short time I had this account, but think its time to move onto Club Penguin where there are no genders, only penguins.