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.
You can't. If you fail the level enough times, the game will send the request for help to your friends and the only way you will know this is if you get a pop-up saying the friend sent some boosters to help.