Q: Apple Pay refused in Apple Store: "Apple Pay is not available in "Apple Store""

I got it to work. You must have your Apple Pay billing address exactly matching what is on file with the credit card issuer. in my case I added my billing address to Apple Pay using the convenient option to fetch it from a contact, and I had one for myself. Problem is, my contact had the zip+4, and I had only given my credit card company the basic zip. After repeated tries, sometimes the error would actually point to the billing address and let me fix it, instead of the generic "doesn't work with this app" message.

Here's the other problem: if you go ahead and fix the billing address from the error message in the middle of your Apple Pay purchase, you can get that purchase to work, but in fact your default billing address remains the same and it will happen again on the next purchase. You  have to manually change the bllling addres using Apple Pay settings. And you can't import a contact and fix it, say by removing the zip+4 part, you have to enter the entire billing address carefully. Actually that it s third problem, when you import a billing address from a contact you should be able to edit it. Hmm, I wonder what happens if I have entered a billing addres ever so slightly differently on different credit cards? That is going to be problematic.

I am sure this will all be worked out. I love having the ability to pay without exposing any credit card details to the merchant. I am about to have to change my credit card for the third time this year, not because I lost it but because an on-line vendor has had a breach of their database (this time home depot), and my credit card company thinks it best to send me a new card. I am going to use Apple Pay or Pay Pal as much as possible for online purchases instead of entering credit card info.