Can I use Apple Pay as back up when I lose my card?
No. Once a card has been reported lost/stolen or is locked, the card is suspended in your digital wallet and cannot be used.
If the card is found and unset as lost/stolen or unlocked, the card will automatically resume in your digital wallet, provided there are no other restrictions on the card.
If a new card is ordered, it will update to the wallet automatically and you can recommence making payments/purchases using your digital wallet.
Apple Pay Terms of Use.
Apple, the Apple logo, Apple Pay, Apple Wallet, Apple Watch, Face ID, iPad, iPhone, iTunes, Mac, MacBook Pro, Safari, and Touch ID are trademarks of Apple Inc., registered in the U.S. and other countries and regions. For a list of compatible Apple Pay devices, see support.apple.com/en-us/HT208531