Client BUG, sorry we are not able to start your game, and then 'Find Match' does not work.

I was playing a aram game, and then after the champion pick, the client suddenly pop up a message, which says ' sorry, we cant start your game', and then when I try to find another match, the ' Find Match ' Button seems like does not work at all. I tried to restart the client or restart my PC, it does not help.

This is the first time I have this kind of BUG happen, and it was quite interesting, because I just complete a Riot survey, which is asking me about the last week play satisfaction, and I put totally disagree, because the client seems like lag than before.