[Crash] Freezes seconds into a match

I have been getting this quite frequently, up to 3-4 times a day. I start a match of ARAM as usual, and then sometimes before i can even purchase any items the game becomes unresponsive. I am using a Macbook Pro, the client is updated to 4.21. I can't say how prevalent this bug is none of my friends have macs but this issue has caused my team to lose their matches when this occurs since i have to restart and relog to get back into the game. I also see that I have been placed into the lower priority queue because of this issue.

Thanks!