This may happen due to the following reasons:-

I) Incorrect details of Credit / Debit Card
II) Card declined from Card Company/Bank
III) Crossed Excess Credit limit available on your Credit Card
IV) Card Company doesn't allow International/Overseas transactions
 V) Mismatch of Shipping & Billing address

In case none of the above reasons are applicable to you, we wish to inform you that, we have multiple options for payment on our website. In case of getting an error message, please try the alternate option on our site.  If the issue still persists you may touch base with our care team and we will be more than happy to help you.