Banned for (potentially) no reason

Just received a 14 day ban, with no prior punishments, for one game.

Game 1 kalrus: if u play liss kalrus: kys kalrus: i cant kill liss kalrus: roaming at 3 kalrus: inspiration and liss R kalrus: sigh kalrus: if i see stopwatch im afk kalrus: sigh kalrus: shoulda hooked kalrus: nas kalrus: just keep stacking for free kalrus: and we win kalrus: liss r kalrus: if u pick a mid with a "oh shit i fucked up" button pls kys kalrus: 2 top kalrus: liss kayle anivia malz swain kalrus: fuck those champs kalrus: lol kalrus: couldnt get on her kalrus: she went invis kalrus: couldnt proc W kalrus: doesnt matter kalrus: they picked vayne karma liss kayn kalrus: cant kill anyone kalrus: wtf kalrus: u healed for ur whole hp bar kalrus: we loseteamfights kalrus: which one of u autists didnt ban vayne kalrus: no kalrus: she has overheak kalrus: and relic kalrus: and bloodline kalrus: she has the effective hp of a tank kalrus: wont matter kalrus: they have vayne kalrus: its gg kalrus: we dont win 131 either kalrus: i cant 1v1 anyone but karma kalrus: great meta kalrus: why do we not ff kalrus: doesnt matter kalrus: im not playing lol kalrus: texting kalrus: waiting for ff

I'm left to assume that the chat filter caught the "kys" and administered a ban? For context, the Lissandra player in question is on the enemy team, and I have /all chat turned off. The "kys" was directed at no one, I was just frustrated at the current meta of waveclear mids with stopwatch. I really don't feel this should be a 14 day ban, but rather a chat restrict, if anything? Could I get some clarification from a Rioter?