Permanently Banned for typing "%%%"

The convo went like. Enemy: "glhf" Me: "k y s" He was like "oooo thats so toxic dude". (SATIRICAL) I stomped top lane as Kennen, wasn't talking a lot in chat. Enemy got mad cus i messed the up hard and reported me because he is mad he lost his lane and boom I get a perma ban. Spent 3000 hours on this game and hundreds of euros this game and I get banned for typing "%%%". How the %%%% is this a deserved ban?
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