Champ select bug

There was this recent issue when I decided to play ranked, upon accepting to join the lobby, the client turned black and i couldn't view anything on the screen. I decided to wait, it didn't go away and when i closed my client reopened it up again. It worked since this takes of LP if you dodge a queue. So i received a penalty for a bug issue. I'm not too sure how it came to be but I do remember this happening to me one other time but it was a long time ago, this is the second time it happened to me. I'd assume that it is a rare case but letting you know that it does exist