Trying to install apps
iMac, OS X 10.11
Question marked as
The resolution to this issue is often making sure you have entered a credit card or other valid method of payment* even if you plan on using account balance to pay for a purchase.
If there is an option to select "Review" or "Continue", select that and enter valid payment information if required. If there's problems doing this, this document explains how to 'Add a payment method to your Apple ID' on an Apple mobile device, a Mac, or a PC; click here --> Add a payment method to your Apple ID - Apple Support
If you continue to have problems contact Official Apple Support - Select your region from the list and then your country from the pop-up window. If you do not see your country, see if there is an "other" listing for that region.
https://getsupport.apple.com/?caller=cups&PGF=PGF63005
*Payment methods that you can use with your Apple ID - Payment methods that you can use with your Apple ID - Apple Support