Warning for Verbal Abuse

I'm not sure how or where I can retrieve chat logs, but I got a warning for "Verbal Abuse" because I muted my whole team at the start of the game for calling me fat and telling the enemy team to report me?

So not only did I not defend myself cause according to Riot that's against the rules and part of being toxic, but I can't mute my team for name calling without them getting upset and making false reports?

Can someone please help me understand? Like I legit muted them before the minions even spawned because they were spamming chat and being toxic and I said nothing to them.