Hi there! I understand you're having trouble adding a new debit card to the Dunkin' app on your iPhone running iOS 18.7. To help you effectively, could you tell me if you are seeing any specific error messages when you try to add the card? Also, have you already tried deleting any existing payment methods in the app before adding the new one?

Meanwhile, here’s a step-by-step approach we can try together:

1. Check Existing Payment Methods: The Dunkin’ app often only allows one payment method at a time. Please open the app, go to the payment settings, and if you see an old debit or credit card saved, try deleting it first, then attempt to add your new card.

2. Restart Your iPhone: Sometimes, a simple restart can clear temporary glitches that prevent adding new details. Hold down the power button, slide to power off, then turn it on again.

3. Update the Dunkin’ App: Make sure your Dunkin’ app is updated to the latest version. Open the App Store, tap your profile, and scroll down to see if there is an update for Dunkin’.

4. Reinstall the App: If updating doesn’t help, try deleting the Dunkin’ app and reinstalling it fresh from the App Store.

5. Verify Card Details: When adding the card, double-check that the card number, expiration date, CVV, and billing address are accurate and match what your bank has on file.

6. Check Your Bank or Card Issuer: Sometimes, banks block new transactions or require additional verification for apps. You might want to contact your bank to ensure the card can be linked with third-party apps like Dunkin’.

If after these steps you still face issues, please let me know if there is any specific error code or message. That would help me to assist you better.

Are you comfortable trying these steps? If you’ve already tried any of them, let me know so we can focus on other solutions!

App won’t let me add new debit card

Thanks for letting me know the issue with adding your new debit card to the Dunkin' app on your iPhone. Since you mentioned it simply won’t let you add the card, let's dig a little deeper with some targeted steps based on recent similar reports.

Sometimes, the Dunkin' app can refuse a payment method if the billing address in your payment info doesn’t exactly match your bank’s records. Have you checked and updated your billing address in the app recently? Some users found that updating their address fixed the issue with adding cards or Apple Pay in Dunkin' 1.

Here’s what I suggest:

1. Open the Dunkin' app and navigate to your payment or account settings.
2. Review the billing address linked to your current or new card. Make sure it exactly matches what your bank has on file.
3. If needed, edit the address to correct any discrepancy.
4. After saving, try adding your new debit card again.

If that doesn’t help, check these next:

- Update your Dunkin' app to the latest version from the App Store.
- Restart your iPhone after updating.
- Try removing any existing payment cards in the app before adding the new one.

If you get any error codes or messages when trying these steps, please tell me what they say. That info can help narrow down the cause. And if you’ve already tried some of these ideas, let me know too so I can suggest something else.

Are you okay with trying the billing address check first?