If you are unable to make a purchase in the game, please ensure that you have provided a correct payment method in the app store that you use. You can find out more about how to set up payment methods in this article.
Please also ensure that your payment method is supported by your app store.
If it is only in our game that you are unable to make purchases and you can make purchases in other apps, then please contact our support service by sending a message from the game. Describe your problem, and we will do everything we can to help you solve it.