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 the steps on the page didn't help, please let us know more details about the issue and also post a screen shot of the error message you get or how the issue looks like.
Did you get connected? I have the same problem with android and can not find how to connect to Facebook. I was playing with friends and now that option is gone.