We're aware of an issue with Facebook purchases for all King Games and our team is on it. 🛠️ Hang tight while we fix things! You can still enjoy the game, and we'll keep you posted once it's solved.
If you ever come across something you are unsure of or don't understand, i'd recommend checking the Wikia page, it has details of all the things in the game. Here's the link for the section on the Sprinkleshell: