How do I update Apple Device Account Number for Apple Pay purchases?

You’ll need to ask your bank that question. Apple does not assign DPANs or participate beyond providing basic iPhone information. Your bank and the TSP are responsible for approving and creating the token containing the DPAN.

Apple adds the encrypted token containing the DPAN to the Wallet app. When a transaction is attempted, your iPhone provides a token with the DPAN and a unique one time use code to the merchant.

Apple Pay works by what’s known as tokenization. The token represents your physical card and is stored in the Secure Element of your iPhone. Each iPhone has a unique SEID (Secure Element Identification).

During the provisioning of your bank card, encrypted data is sent by your bank to their Token Service Provider (TSP). The TSP creates the token and sends it to Apple servers and it’s added to the SE on your device.

Each token has a unique Device Primary Account Number (DPAN). The DPAN is different for each device the card is added to. So, if added to multiple iPhones and/or Apple Watches, the user and the bank can distinguish which device was used for the transaction.

When adding a new card to Apple Wallet, your bank and TSP will assign it a new DPAN for fraud prevention purposes.

So, now you know more than you ever wanted to know about Apple Pay and DPAN’s. Apple has literally nothing to do with the number change. I’m sure your bank can assist with the exchange/return at the merchants.