How can I resolve the In-App Purchase error?

Dear Apple Support Team,

I am encountering an issue with in-app purchases on my device. Whenever I try to complete a purchase in the eFootball game, I receive the following error message:

“Your Purchase Could Not Be Completed. For assistance, contact iTunes Support at www.apple.com/support/itunes/ww/.”

I have already ensured that my payment method is valid and up-to-date, but the issue persists. I would appreciate your assistance in resolving this matter.

Thank you for your support.

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