Bonus Mystery Skin Promotion

With the recent Mystery Skin promotion that finished about a week ago, on August 10, We were offered a bonus Mystery Skin for every 6 Mystery Skins/Chests bought during the time they were both available. The bonus skins were supposed to roll out today, August 17. I had purchased at least 12+ mystery skins during the time there were available, and only got 1 Bonus Skin, even though I should have at least gotten 2, since I bought at least 12+ during the promotional period.