"You are not eligible to create a lobby for this queue"?

https://i.imgur.com/Xre7fv0.png

I queued up for ARAM, and the second before the game started I got a message "Sorry, we were unable to create/start your game". I think that it's a weird bug, but whatever, I'm gonna try again. Now no matter what queue I click, it won't let me get into a lobby, it just displays the message "You are not eligible to create a lobby for this queue". Resetting the client doesn't help. What happened?