Champ Select Premature Leaver Buster

I qued up for a ranked game, right? Got into champ select, right? Clicked on my champion I wanted to play. Select timer gets to about 10 seconds remaining and I was instantly booted for failing to select a champion. Lost 3 LP and got a leaver buster timer. This has only happened once, I'm... Naut sure what happened but... Just want to put it out there in case anyone else ever had this problem.