Why my address is not working for the Apple Card application

This article also provides some good information:

How your Apple Card application is evaluated - Apple Support

Note that a non PO Box Residential Address is specified.

Presumably any address used should be formatted and verifiable using the USPS’ zip code lookup tool available here:

https://tools.usps.com/zip-code-lookup.htm?byaddress

See “See if you’re eligible” here.

How to apply for Apple Card - Apple Support

If indeed you are eligible, tell us more about your address’ format.