Got banned for 14 days

I got 14 day suspension on my account for being toxic. I haven't had any other bans or chat restrictions ever, so I didn't expect this. I was in a premade with my two brothers and two other friends i know irl. I know its not something to joke about, but i said kys to my friend three times. Its not in a serious way, ive known this guy for 10 years and hes been my best friend for the longest time. Like, cmon none of us take it seriously and im in a game with 4 people i know in real life. Riot support says there are no changes to bans that the instant feedback system makes, but shouldn't there be some exceptions, like I wouldnt ever say something like that to someone i don't know personally. I dunno it was dumb to say but i don't think it deserves a 2 week ban

Edit: That game I called the enemy kat a pu**y, and was probably reported by her or another enemy. I wasn't reported by my teammates (premade) but her report probably flagged the game which detected the "kys." I don't think what I said in all chat was a good thing to say, but it doesn't warrant a 14 day ban.

So pretty much tldr; I was reported for calling the enemy a "pu**y" but the system detected a joking "kys" to a long time friend (in a 5 man premade) and hit me with a 14 day ban.