Riot, there is a serious bug on dynamic queus/champ select

Basically today I connected to play, and while I was waiting for the queue timer I went to check out my profile and I noticed that I got a loss on ranked placement, which surprised me a ton since I was waiting some extra days before entering ranked play I went to check out what was the ranked game I lost, since I could have maybe overlooked some game request during the IP boost weekend and exchange a normal draft for a ranked game, and I found the ranked game that it show me as the lost game... the only problem is that, for my big surprise, it is a game on Kennen which is a champ I am testing these days and I haven't bought yet (I was waiting the end of the free week to buy him) ** TL; DR The system allowed me to play a ranked game on a champ I don't own**

This is my game history, and if you check out my account you can see that I have not bought Kennen yet

http://www.lolking.net/summoner/euw/48844279#matches

I don't know if it was actually a bug in which there was a problem in recognizing the correct queue for the system and actually it uncorrectly classified a normal draft game as a ranked game (this could be a rare event), or even worse the system allowed me to play a game with a champ I don't own, but the result is the same, there was a big fail in the system that resulted in me having a ranked loss on a champ I technically don't own

I don't really care that much about that loss, to be honest, as it is not the end of the world (I wasn't super good and my team was also super toxic and stupid that game, just something that happens at times), but the big problem is if this bug persist in the future and affect future games of many people out there that could just found theirselves in a ranked game alongside a guy that is trying out a new champ they don't own and enter a ranked game without even notice it and thus drag down the entire team

P.S. Sorry for posting it in the wrong sub-boards at first glance