Why do I get the address mismatch error?

try these

1. Sometimes if you sign out of your Apple ID and back in it resolves the problem.
2. Make sure you are using the latest iOS/macOS update.
3. Make sure that your date and time is correct under Settings > General > Date & Time.
4. Make sure that you are connected to a known-good network and are not connected to a VPN.
5. Make sure that push notifications are set up correctly: Use notifications on your iPhone, iPad, and iPod touch.
6. Make sure that your zip code is accurate under Settings > [your name] > Payment & Shipping.

Address changes

on iPhone

1. Go to settings>Wallet & Apple Pay>transaction defaults>address - update as needed
2. Go to Wallet app>tap on any card>tap three dots in corner>tap address - edit as needed for all cards
3. Go to settings>Apple ID (your name at the top)>payment & shipping>address - edit as needed.

on Mac

open Music>select iTunes Store on the left menu>go to the bottom where it says account>sign in>address - change as needed.

on PC

open iTunes and the rest of the instructions should be the same as for Mac.

I am having the same problem. Do you have the 9 digit zip code on your card? Do you abbreviate: St, Dr, or Ave, etc? I have tried to enter or delete last 4 digits of zip but nothing seems to work. I also make sure Drive in my address is spelled out. Again nothing works. I initially thought it was my local bookstore's online software that was the problem. They are investigating. Now it has happened with another vendor with an ongoing monthly charge. Worked for the past 3 months. Now there is an address mismatch. I had not changed the address on my card nor with the vendor between the last "good" payment last month and now. Please let me know if you get this resolved and I will as well. I will contact Apple (Goldman Sachs) again.