Ranked Games Having a Champion Selection Error

Alright, so this has happened to me 5 times in the past 2 months. 3 of the 5 times I have been in my promos. So, it's very frustrating when I go to select a champion and press Lock In but I am unable to do so, or sometimes, the Lock In button isn't even available, it's just grayed out. This is very tilting when I lose LP or a game is thrown away in my promos simply because of this bug. I don't have any screenshots of it, but if it happens again, I will be sure to follow up on this discussion thread. I'd just like to know why something that isn't in my control, and is 100% Riot's fault, punishes me and tosses away my LP and makes me sit in a dodge timer for something that I have no control over.