How do I update the expiration date for my apple pay payment card?

Usually, your bank should automatically update it for you in the Wallet App. If they don't support automatic upates, you would need to remove the card entirely and add it again.

click here ➜ Change or remove the payment cards that you use with Apple Pay - Apple Support

Hello ~Take a look by clicking on below…

Update your cards in Apple Wallet - Apple Support*

*Update your Apple Pay card number and expiration date

With Apple Pay, your payment card has a unique Device Account Number used to process payments and an expiration date associated with that Device Account Number.

If your card expires or you otherwise get a new card:

• The card number and expiration date linked to the Device Account Number should be updated automatically. 
• If your card issuer doesn’t support these updates, you might need to remove the card and add it again.

~Katana-San~