When I try to add a credit card to my new Mac, wallet keeps telling me the expiration date is incorrect. I called my credit card issuer and they said nothing is wrong with my card. I have been able to add other cards, but not this one.

Hello mary jo from in,

You'll also want to make sure that your Mac is running the latest version of macOS using the steps below per this resource: If you can't add a card to Apple Wallet to use with Apple Pay

1. From the Apple menu  in the corner of your screen:

• Choose System Settings. Then click General in the sidebar, and Software Update on the right.

• Or choose System Preferences. Then click Software Update.

2. If Software Update finds new software, click the Update Now or Upgrade Now button to install it.

3. Enter your administrator password, if asked. During installation, your Mac might restart, and you might see a progress bar or blank screen several times.

You can also find those steps in this resource: Update macOS on Mac

Should that still persist, you'll want to reach out to Apple Support: Contact - Official Apple Support They'd be in the best position to look into this further.

Take care.