Can't update payment method

Use the link (the blue text) near the top of this page and follow the instructions to add a new card. And here are some additional thoughts:

There are a number of reasons a charge or verification might be declined:

1. Insufficient balance or account in arrears
2. Account suspended for suspected fraud (not necessarily by you)
3. Error in card number
4. Wrong expiration date
5. Wrong security (CVV) code
6. Address in your iTunes account does not match exactly the billing address for the card
7. The card was not issued in the country of the iTunes store
8. You are connected through a VPN provider that does not terminate in the country of the iTunes store you are connected to.

It’s not all that smart to post a credit card number in a public forum viewable by millions of users. Watch out for fraud on the card and report any immediately. I’ve asked the forum hosts to remove your image.