Can't buy anything on iTunes

Basically the subject title; I'm using Windows.

All of a sudden I can't buy anything from iTunes; I received my Apple card the other day and have made it my default payment, so I updated my payment method. Now my purchases won't go through:

When I tried making sure my iTunes was up to date, the help section said updating it can be found under the Help menu: But there is no update option under the help menu.

I went to the Apple.com website to check on updated versions of iTunes to just download it manually, but the lastest version I found was 12.10.11, mine seems to be newer:

I'm at a loss for what to do now. I've made sure all the little things were in order (payment information, address, etc.). Devices are authorized; I've looked for updates as best I could and it seems I'm up to date; nothing helpful in the Microsoft Store.

Any ideas on what to do?

Thanks!