It's because you inted/flamed/were too negative in chat. So..... Don't do it.
I had my main account perma banned. Yes, I got warnings earlier like everyone else... I tried to tone it down in game... I guess still not enough.
Lost all my Legacy Skins, Mastery Points, Wards, Champions, etc..... Very bitter because I was honestly trying to follow a good path and gain honour.
I apologize to the community for any grief I caused anyone in game through chats. I will always be following the summoners code from now on.
To anyone who is currently under a temp suspension, chat restriction etc... STOP. Just don't use chat if you are prone to using it "too much".
Since my main was perma banned, I have ranked up HIGHER with a new account than I was before... This was due to FOCUSING ON THE GAME instead of chatting and also with ME taken out of the picture for chat, the flaming on my entire team DECREASED during every game all around leading to MORE WINS.
So again.... If you are prone to feeding or even get mad or negative in game... Don't Do It.
Again, I apologize to anyone i have ever flamed in game, or here on the boards.