I want to pay for apple store app

If your payment method is declined in the App Store or iTunes Store

You can't make purchases or update apps until you change or update your payment method.

If you have an unpaid balance in the App Store or iTunes Store, you might see one of these messages:

• "There is a billing problem with a previous purchase. Please edit your billing info to correct the problem."
• "There is a billing problem with a previous purchase. Click Purchase History to view and correct the problem. If you cancel you will not be able to buy until this billing issue has been resolved."

To resolve this, add a new payment method or update the billing information for your current payment method. Your unpaid balance will be charged. Then you can make other purchases and update your apps, including free apps.

Find out why a payment method can’t be charged

When you view your list of payment methods, you might see red text that summarizes why the payment method couldn't be charged.

If something is wrong with the primary payment method that you have on file, a different payment method will be charged. Learn about how purchases are billed. 

If none of your payment methods can be charged, your last order will remain unpaid. View your purchase history to see your recent purchases and find out which order is unpaid.

Update or change your payment method

You can update your billing information or add a payment method in Settings on your iPhone, iPad, or iPod touch, or in iTunes on your Mac or PC. If there's an issue with the billing address or expiration date, tap or click the payment method, then update the payment information.

If you change your payment method, use a valid payment method in your country or region with money available on it. To prevent unpaid orders in the future, you can add multiple payment methods to your Apple ID.

If you use Family Sharing and you see a message about a billing problem with a previous purchase, the family organizer must update their billing information.

If you see an unexpected charge

You can request a refund* for a purchase that you don't recognize, but you must pay for the purchase first. You can also cancel a subscription if you don't want to continue it.

*Refund requests must be in the refund period and refunds are not guaranteed. For more information, see the Terms & Conditions.

If your payment method is declined in the App Store or iTunes Store ...

https://support.apple.com/en-us/HT203005

Try a different card (credit cards are more likely to work than debit cards).

For a card to have a chance of being accepted it needs to be registered to the same name and address (including format and spacing etc) that you have on your iTunes account, and have been issued by a bank in the country where you are (and therefore the country which is on your iTunes account).

You may have money on the card, but that doesn't mean that it will automatically pass the iTunes validation and that you will be able to use it on your account.

What you are entering may be correct, but that obviously doesn't mean that it will pass iTunes validation and that you will be able to use it on your account.