Apple payment methods

And to add to what LACAllen has provided, you cannot delete a card until you have added another valid card. See this, Change, add, or remove Apple ID payment methods - Apple Support

If your payment method is declined in the App Store or iTunes Store - Apple Support

Apple is declining a card and will not let me delete the card or make an update and do not know how to do, someone help me?

Apple is not declining your card.

The card issuer is declining your card.