I am unable to get the add on services from the credit card

I am not able to buy add on services

after adding my plan into the cart in the payment screen where OTP need to verify amount is 0 and even i verify the OTP my screen language in the page where it says we are "unable to process the payment due to an unknown issues with the card please try a different card or a different payment method if the issues perfect please contact your bank"

my card is enable for international payment, Merchant Payment, Web Purchase.