The most likely cause for the error in this case is that the merchant's script is replying with an empty string. This indicates that the merchant has not completed the payment button installation.
When someone clicks a payment button, all the purchase information in the merchant's form is sent to the Ezybonds server.
The Ezybonds server then sends a 'CHECK' notification to the merchant's notification script.
The merchant's notification script is controlled and hosted by the merchant. The 'CHECK' notification allows the merchant to review and verify each purchase/payment request made via the payment button.
The merchant's notification script must then reply with either of the single words 'CONFIRM' or 'DECLINE'. If this confirmation is not received an error message is generated.
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