Why i cant add card in my wallet?

Any error messages given?

Did you already try the troubleshooting mentioned in this related article?

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Learn what steps to take if you can't add a card to the Wallet app to use with Apple Pay.

1. Check that you're able to use Apple Pay:

• • Contact your card issuer to see if they support Apple Pay.
  • Update to the latest version of iOS, watchOS, or macOS.
  • Confirm that you have Face ID, Touch ID, or a passcode set on your device. 
  • Make sure that you are in a supported country or region.
  • Check that your device is compatible with Apple Pay.

2 . Check for service outages or connection issues.

3 . Contact your bank or card issuer if you see the following error messages while adding your card to Apple Wallet: 

• • Could Not Add Card 
  • Invalid Card 
  • Card Device Limit 

Apple does not approve or decline cards for use with Apple Pay. If your card was declined, contact your bank or card issuer.

If you need help adding a card, learn how to set up Apple Pay.

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copied from: If you can't add a card to Apple Wallet to use with Apple Pay - Apple Support