Hextech Chest not dropping after achieving an S rank [GAMEPLAY]

Between yesterday and today I managed to achieve S- rank or S rank with Miss Fortune three times and I didn't receive even one hextech chest for the achievement. I also didn't receive the Mastery token for the third time I got above A+ rank.

Any way I can get rewarded for this? I dunno if Riot has a back up of every game on how it ended, but its three S ranks and no chest at all.