Champion Select Picking the same champ

Hello i was in a blind pick lobby and at the very last second me and another player randomly selected the same champ, this being Nami. For a split second it looked like i was thrown out of the lobby before it reloaded the lobby with the first screenshot in the link being what i was met with and attempting to close the client gave my the warning in the second image.

Typing in chat just deleted whatever i typed when pressing enter, a message also popped up when i tried to select a champ yet i forgot to take a screenshot before closing the client, i believe it said another player has chosen this champ sorry about that.