Merge Sticker Album Star Vault Not Working as Stated

Thanks to GritySuesue1, I went back and checked the info about the Star Vault in the Sticker Album.

For 100 stars it says, "Guarantees a tier 3 sticker you don't own yet!"

Here is the screen shot from Monday. I was disappointed that I got three duplicates and didn't even realize I was supposed to get a 3 star sticker, but did not.