I have available balance in my account, i can’t buying any app

Here are some reasons why you might not be able to purchase an app from the App Store even though you have an available balance in your Apple ID account:

• Your account may be restricted. If your account has been restricted for any reason, you may not be able to make purchases. You can check your account status by signing in to your Apple ID account online. If you see a message that says 'Your account has been disabled in the App Store and iTunes'
• The app may be more expensive than your balance. Make sure that the price of the app is less than or equal to your available balance.
• Your payment method may be declined. Make sure that your payment method is valid and that you have entered the correct billing information. You can check your payment method settings by going to Settings > Apple ID > Payment & Shipping. If your payment method is declined in the App Store or iTunes ...
• Your bank may have imposed some new limitations on your Card.
  • You have exceeded your credit limit. If you have used more than your credit limit, your bank may have placed a hold on your card to prevent you from spending more money.
  • Your card has been reported lost or stolen. If your card has been reported lost or stolen, your bank may have temporarily blocked your card to prevent unauthorized use.
  • Your card has been flagged for suspicious activity. If your bank has flagged your card for suspicious activity, they may have placed a hold on your card to investigate the activity.
  • Your bank is undergoing a security upgrade. Sometimes, banks may impose temporary limitations on cards while they are undergoing security upgrades.
  • Your bank may have withdrawn international transaction facility for your account

If you have checked all of these possibilities and you are still unable to purchase an app, you can contact Apple Support for help.

Here are some additional things you can try:

• Make sure that you are logged in to the correct Apple ID account.
• Try updating your device's software.
• Try restarting your device.
• Sign out of your Apple ID account and sign back in.

Here are some specific steps you can take to troubleshoot why you can't purchase an app from the App Store even though you have an available balance in your Apple ID account:

1. Check your account status. Go to Apple ID account status: Wireless carrier support and features for iPhone in the United States and Canada - Apple Support and sign in with your Apple ID. If your account is restricted, you will see a message that says "Your account is restricted."
2. Check the price of the app. Make sure that the price of the app is less than or equal to your available balance. You can find the price of the app on the app's product page in the App Store.
3. Check your payment method. Make sure that your payment method is valid and that you have entered the correct billing information. You can check your payment method settings by going to Settings > Apple ID > Payment & Shipping.
4. Check the App Store status. If you are having trouble with the App Store in general, you can try restarting your device or checking the App Store status page. You can find the App Store status page here: App Store status: Apple - Support - System Status
5. Check your credit card statement. Your credit card statement will usually show any recent changes to your credit limit or other limitations on your card.
6. Call your bank. You can also call your bank to inquire about any recent changes to your card.
7. Check your online account. If you have an online account for your credit card, you can usually check your account to see if there are any recent changes to your card.

If you have checked all of these possibilities and you are still unable to purchase an app, you can contact Apple Support for help. You can contact Apple Support by phone, chat, or email. You can find the contact information for Apple Support here: Apple Support contact information: https://support.apple.com/contact.