Not able to pay an unpaid order.

I understand your frustration with the ongoing billing issue in "Cookie Run Kingdom." It can be quite disheartening to have a pending payment for so long. Here are some steps you can take to resolve this matter:

1. Contact Cookie Run Kingdom Support: Reach out to the game's official support team through their customer support channels, such as email or in-game support options. Explain the situation in detail, including the declined purchase, the gift card balance, and your inability to add funds to your Apple Account.
2. Provide Payment Details: Once you've contacted support, be prepared to provide them with your payment information, such as the last four digits of the declined card number and the expiration date. This will help them verify your identity and investigate the issue further.
3. Check for Gift Card Restrictions: Some gift cards may have restrictions that prevent them from being used for in-app purchases. Verify the terms and conditions of your gift card to ensure it can be used for "Cookie Run Kingdom" purchases.
4. Update Apple Account Payment Information: If you're unable to add funds to your Apple Account, check your account settings to ensure the payment information is up-to-date and valid. Try removing and re-adding your payment method to refresh the connection.
5. Consider Alternative Payment Methods: If the gift card or Apple Account options aren't working, explore alternative payment methods, such as PayPal or direct carrier billing. These methods may have different restrictions and compatibility, so it's worth checking their terms of service.

Let me know if you need anything else to ask!