I have money on Apple ID but won’t allow purchases

Have you ever had a payment method is declined in the App Store or iTunes Store https://support.apple.com/en-us/HT203005?

Do you have a credit large enough to cover the cost of the app plus any local sales taxes?

ASC - Late 2012 Mac mini, macOS 10.15.4; Watch, series 5 GPS/cellular, watchOS 6.2; iPad Air 2, ipadOS 13.4; iPhone 8+, iOS 13.3; TV 4th Gen, tvOS 13.4;  HomePods, audioOS 13.4 and Airport Express w/ Airplay 2