Problem with payment in appstore

Have a look at this article: If your payment method is declined, or you have a billing issue in the App Store or iTunes Store

Update your billing information

You can update your billing information in Settings on your iPhone, iPad, or iPod touch, or in iTunes on your Mac or PC. When you update your information, use any of these payment methods. You can't select None when you have an unpaid balance or payment due.

After you update your billing information, the App Store or iTunes Store automatically attempts to charge any outstanding orders to your updated payment method.

Pay an unpaid bill

On your iOS device: Go to Settings > [your name] > iTunes & App Store, then tap your Apple ID. Tap View Apple ID and sign in with your Apple ID, then tap Purchase History. (You can also view your purchase history in iTunes on a Mac or PC.)

Find the unpaid purchase, which is likely at the top of the list, and tap it, then change your payment method.

Add funds to your Apple ID

When you try to pay an unpaid bill, you might see the option to pay with Apple ID credit if you have a credit balance.

If you don’t have a credit balance, you can redeem App Store & iTunes Gift Cards or add funds to your Apple ID2, then use the credit to pay an unpaid bill.

If you were billed unexpectedly

After you pay for the purchase, you can Report a Problem if you still have an issue with the purchase. You can also cancel a subscription if you don't want to continue it.

If a child or minor has access to your device, you can set up parental controls and restrict their in-app purchases. If the child or minor has their own device, you can also set up Family Sharing to control what they buy on their device.