Game crashes at beginning of almost every game on Mac

This has been happening for over a month now, it's super frustrating. Usually happens at the very beginning of the game, right around when the first minion wave reaches lane. I have been in contact with support but they couldn't help me. They said it was my schools internet blocking the game, but when I talked to my school's IT service they said there is no reason it shouldn't be working, consider tons and tons of kids play league at my dorm and have no issues. Also I am now playing at home on a completely new internet system and it is still happening. I'm guessing it has something to do with the new update, it's frustrating because I pretty much can't play ranked without losing the game for my entire team.