Where are my Champs?

o I bought several champions during the past week. Upon logging on today, the champions i bought just disappeared and has been put there as "unowned". I did not get my blue essence back either. I actually managed to play ranked before and currently doing my placements. I have done 3 out of my 10 games and is currently placed in Bronze 1. But now I cant even play anymore because apparently I do not have enough champions. I had exactly 20 before and now I only have 15.