PAYMENT DECLINED UPDATE BAILING INFO

Know it here --> If your payment method is declined in the App Store or iTunes ...

Check the following

1. The payment method that you are adding is of the same country as that of App Store Country on your iPhone
2. You have a valid payment plan debit/credit card from an authorised bank from the same country
3. Payment methods that you can use with your Apple ID - Apple Support
4. Learn more about family purchases and payments.
5. Please check if your Debit/Credit card is valid internationally

Hey there,

before contacting Apple support , make sure that the information of your billing address is Compatible with your payment method, after that if you still can’t add your payment method Contact Apple for support and service - Apple Support