Apple Pay shipping address invalid - how to fix or update?

Hi, Just solved this for my case and wanted to share it with others, it was driving me nuts. The case is that your apple pay works at grocery stores and gas stations but when you use to purchase something inside an app like a new vendor app, restaurant, or transit company you get a Billing Address Invalid error message. What it is comparing is the billing address your credit card company has for you and the billing address on Apple Pay on that card (Setting -> Wallet &Apple Pay -> apple pay card -> Billing Address) . I changed my billing address on my Apple Pay card on the iphone (I found the Apple web app wouldn't change it) and it worked. I noticed my credit card company had all caps for my address so I changed the Apple Billing address to all caps too. On the Apple address I also had a period (.) after BLVD and I took that off. One of those two things worked. Another key to solving this is having an in app payment (small amount, let's you back out after the card is verified) that you can use repeatedly. You will need some trials to fix this problem.

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