This may happen due to the following reasons:-

I) Incorrect details of Credit Card

II) Credit Card declined from Credit Card Company/Bank

III) Crossed Excess Credit limit available on your Credit Card

IV) Credit Card Company doesn't allow Overseas transactions

V) Mismatch of Shipping & Billing address

For further assistance, please contact your respective bank.

If the problem still persist, please touch base with our Customer Care team and we shall be more than happy to assist you in the best possible manner.