Blocked after leaving Champion Selection

So, inadvertently I was trying to get into a Normal - Draft pick game. Took about 11 minutes to get in due to other people who kept leaving during champion selection. The third time it happened again but it said I left the selection!? WTF??? I didn't so now I am posting to see if anyone else has had this happen to them. I was literally typing into the chat box when it randomly booted me from champ select. I even already had my champ picked.

I was of course blocked for the 6 minute or whatever it is which is not much time but I want to know how this happened?