A possible reason for seeing this message is Apple cannot find a functioning payment method (usually a credit or debit card) to use in association with making this purchase. You may not have adequate balance. Even if you do have adequate balance, Apple may require a payment method be present on your account (particularly if you are starting a subscription or trial). Even free apps may require the presence of a payment method, although it won't be charged if they are free. Some items cannot be purchased with account balance.
Use the document Add a payment method to your Apple Account - Apple Support to review your payment methods such as credit or debit cards. Problem methods will usually have a notice in red lettering below them. The article: If your payment method is declined in the App Store or iTunes Store - Apple Support has some information about declined payment methods.
For information about updating payment methods on various platforms (iPhone, Mac, etc.), click here --> If you need to change or update your Apple Account payment method - Apple Support
If there's an issue [such as you having a subscription or being a Family Sharing Organizer], add a new card first, then remove the old card.
If using Apple Account balance to pay for an item, ensure there is adequate balance to pay for the item, including tax if applicable. Read this article about how to check your Apple Account balance.--> Check your Apple Account balance - Apple Support Some purchases may require the presence of another payment method such as a credit card even if the final payment will be made by account balance.
If it is not a payment method issue, Apple may have placed a block on your account for other reasons. In that case do as Apple says and contact them. There is nothing more that anybody on this forum can do than advise you to do that. I personally have found Apple's contact method in this situation somewhat confusing and leading me in circles. Try this:
-Click on this link —> Choose your country or region - Official Apple Support
-Choose your country from the list.
-Scroll down the page to “Get Support” and click on “start now”.
-Scroll down to “Get more help” in the bottom left and click on it.
-What you see will depend upon the support types available in your country. You will hopefully get a chat session.
If that fails to work, this support article has various country telephone numbers for contacting Apple for support and service ➔ Contact Apple Support - Apple Support
I'll add that I have seen several threads recently where people carrying large balances have reported this issue. They absolutely had to have it resolved by contacting Apple.
