I'm having a really frustrating issue where I can't add my debit card as a payment method on my iPhone. Every time I try, it declines. Furthermore, when I try to use Apple Pay for Apple products like iCloud+ or Apple TV, it also gets declined. I contacted my bank, and they mentioned it could be a security issue, and that I needed to ensure that all my information (like my address, card number, and phone number) matches perfectly. I've double-checked everything, and it all seems correct. Interestingly, I can use Apple Pay without issue for non-Apple products or services.
I also reached out to Apple Support, and they told me they would fix it, advising I wait 24 hours to try again. It's now been over 24 hours, and I still can't add my card. I actually tried this issue with a previous card too, and although I got a new card that worked for a bit, it's now declining again. I'm running out of ideas and hoping someone might have a solution.
4 Answers
How often have you been trying to add the card? I had a similar problem when I was switching cards on my new iPhone. I think my bank's authentication service was down for a few days, which caused the issues. So, it might be worth trying again after waiting a bit.
Just curious, have you ever done any chargebacks with Apple? If you have, that might explain why you’re having trouble. Apple or your bank might have flagged your account due to that. But if you haven’t done that, I’d think they would have informed you.
Have you checked if the billing address on your Apple account matches the one on your card? Sometimes this can be the culprit, especially if there’s a discrepancy in the country or postcode. I experienced something similar, and updating the address fixed it for me.
Is this happening with all debit cards, or just the one you’re trying to use? Since a debit card links to a checking account that can potentially be overdrawn, there might be some restrictions there? Might be worth exploring this angle.

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