Why does my credit card payment fail?

Answer: 

Sometimes online credit card transactions would fail - the reasons for such failure may simply be the use of a wrong card number or the card limit has been reached, etc. In other cases the reasons are less obvious and may relate to the ever increasing fraud prevention and/or other security measures implemented by credit card companies to protect the cardholder against card abuse.

Do carefully check the card details and billing address before confirming the transaction for processing. Also ensure your card is actually a credit card and not just a debit card. 

A list of common reasons why payments fail:

Your card doesn't allow international transactions:
If you're making payments from abroad, make sure your card accepts international charges. If it doesn't, ask your bank to change this or use another card.

Billing address:
Make sure that the billing address you use for the transaction matches those that your credit card company has. Address matching is however not very likely to be the main cause of a transaction failure.

Your credit card limit was reached (insufficient funds):
Check your credit limit. You might have reached your daily or total credit card limit on the day you tried to charge your card. If this is the case, ask your credit card company to increase your limit.

The charge exceeded the maximum amount allowed for a single charge:
Check the maximum amount your card can be charged at a single time. If the declined charge is higher than this amount, ask your credit card company to increase the limit

Your card reached the maximum number of charges allowed in a period:
Check how many times your card can be charged in given time period. If you reached this amount, ask your bank to increase the limit, wait until your card can be charged again, or make a payment with a different payment method.

Your card doesn't accept charges from an online source:
Make sure your card allows online transactions. If it doesn't, talk to your credit card company about allowing these charges. Or use another card.

Wrong expiration date:
Review the expiration date on your credit card. If your card expired, use another card
Wrong credit card number
You should get an error message indicating the card number is not valid. If not, carefully check the card number when filling out the form.

unauthorized:
If the above reasons are excluded, it may be due to the risk assessment of your bank card, and it is impossible to confirm whether your transaction was initiated by yourself, so you need to contact the bank to indicate that the transaction was indeed initiated by you and authorize the payment. Then notify us for a second deduction.