If you cannot make a purchase in the game, please try adding or updating your payment method.
  1. Open the Google Play app.
  2. At the top right, tap the profile icon.
  3. Tap Payments & subscriptions -> Payment methods.
  4. From here, you can do these things:
    - Add a payment method — Tap Add Payment Method.
    - Update a payment method — Tap the payment method, then edit your information.
Once you have added or updated your payment method, log in to the game again and make the purchase. If you're still having problems making purchases, please contact the Google Play Customer Support here ("Contact Us" button).