All my cards are being declined by Apple

So sorry, I understand this can definitely be frustrating.

So if your payment method is declining in the iTunes and App Store : https://support.apple.com/en-us/HT203005

I would check your purchase history and verify that there isn't any pending transactions that need to be paid for.

Sometimes if you owe something, you may not have that amount on the card to cover it and plus what you are trying to purchase.

You may need to update your payment method : https://support.apple.com/en-gb/HT201266

Check Purchase history : https://support.apple.com/en-us/HT204088

Hope this helps

A “payment 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:

• 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.

If it was suddenly declined when it had been working contact your card issuer.

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

See this, If your payment method is declined in the App Store or iTunes Store - Apple Support

I'm facing the same issue. Did you tried after some hours of declining. I tried many times on the next day I just made a purchase and later on I tried and it work for me. May be it need some time due to some error ,etc.

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