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 need to request tickets to progress from your friends. There have been some problems with it so I made a video showing how I was able to get through. Hope it helps.
https://www.youtube.com/watch?v=eoXtJPMIG6I