While buying on Iconfinder or being charged for the renewal of your Pro subscription, some payments may be unsuccessful. If this happens, Iconfinder will return an error code that informs you what the problem with your credit card might be. Please visit the article on Reasons why credit card payments fail for more information. 

For subscriptions, Iconfinder will retry the charge a few times during 30 days. If we don't succeed at renewing your subscription, it will become paused. Read more about Paused subscription and about our Policy for unpaid subscription periods. 

This means that there is not enough money available in your bank account to pay for your purchase or subscription on Iconfinder. In other words, what you are trying to buy costs more than what you have in your bank account. 

Solution: Refill the funds on your bank account in order to fix this error. If that is not an option, you can add a new card to your Payment settings. and retry the payment. Contact customer support if you want to use another payment method.