I forgot my Apple Pay pen number

I’m not sure what a pen number is, unless you mean a Personal Identification Number (PIN). Apple Pay does not have or require a PIN, so I’m not sure what you are asking, either. It is a way to use credit and debit cards with your phone.

That would be the PIN for the debit card you are using. It is not a PIN for Apple Pay. As I said, Apple Pay does not have any PIN requirements beyond the requirements of the card you are using.

If you mean the CVV security code for use with an Apple Card, tap on the Apple Card in Wallet, then on the icon with “123” at the top of the screen.

Some retailers require the debit card/credit card PIN when doing any contactless payment method, whether it’s Google Pay or Apple Pay.

In any case, there’s nothing we or Apple can do anything for the original poster.