Level 6 Mastery Token NOT GRANTED if S is received during the game in which level 5 was acheived??

Has anyone else had this problem?

I reached level 5 mastery with Irelia, and happened to get an S on that same game. It told me that i had received a token for her lvl 6 Mastery, but it is not in my Hextech inventory. I was wondering if this was a glitch, or if because I hit 5 and got an S at the same time, that it didn't actually give it to me.