cannot verify payment information
Tried to update my payment method within the App Store on my MacBook Air, but when I enter my (correct and valid) credit card information, a pop-up window says "Cannot Verify Payment Information" and says to contact Apple Support. When I contact Apple Support, it just leads me back to the App Store window where I can supposedly update my payment method, except I can't, since it keeps saying it can't verify my payment information.
MacBook Air 11″, macOS 10.13