Account password changed, (Possible Email Hack)

So about a few years ago I enlisted in the military. Haven't had time to play because of my duties. The account in question is the one i'm on. Earlier this week I tried to log into this account. It kept saying wrong password. I tried to get another password resent but nothing. I checked my inbox my spam nothing. So I opened a support ticket. I wasn't really expecting what happened. Now please rest assure i've had this account since late season 2 almost. Right around when season 3 was about to start. Had the honor symbol on my card and everything. Before we got to season 5 is when I stopped playing. I was directed over the behavioral team. That's odd I thought. Then they proceed to tell me my account has been perma banned. So, going back and forth with this riot support agent. I'm trying to get through to this person that I couldn't get in. She keeps telling me over and over again she doesn't see any suspicious activity.

Finally, she put back me over through to the recover account team. I got back in my account cause they sent me the verify email link and change password link and sure enough there is a chat log full of so much toxic i've never seen anything like it.

Now what's interesting is, I have tons of alerts from Yahoo preventing sign in attempts to my email. And I sent screenshots to them as well of this.

I'm just trying to figure out what the heck happened. Shouldn't they be able to see the IP Address that was playing on the account or something? Because I was not expecting to come back and see my account being banned like it was. Has this ever happen to anyone???