Trying to update payment method after previous card information was defrauded.

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You must add the new card before removing the old card. If you have a problem adding the new card contact the card issuer. If it declines the card a “card declined" message means that the issuer of the credit or debit card you have on file in your iTunes account rejected a charge or account confirmation. It is not an Apple problem; Apple is just passing through the message from your issuer. There are a number of reasons the charge or verification might be declined:

• Apple is not allowed to accept credit or debit cards in your country
• The card is not recognized in your country
• Insufficient balance or account in arrears
• Account suspended for suspected fraud (not necessarily by you)
• Error in card number
• Wrong expiration date
• Wrong security (CVV) code
• Address in your iTunes account does not match exactly the billing address for the card
• The card was not issued in the country of the iTunes store
• You are connected through a VPN provider that does not terminate in the country of the iTunes store you are connected to.

Here is additional information from Apple→If your payment method is declined in the App Store or iTunes Store - Apple Support