NMI Error 430: Duplicate Transaction

What This Means

By default, NMI rejects any duplicate transaction within a 1200 second (or 20 minute) window.
A duplicate transaction is any transaction executed with the same amount and card number.

Suggested Next Steps

  1. You may check for more information on this specific transaction and decline within your NMI web interface by visiting Reports >> All Transactions.

  2. If the transaction was completed and the payment was successful, you should check to see if the Scheduled Order did actually process successfully.

    • If the payment was successful, ensure that the next occurrence date for the Scheduled Order is updated to the accurate future next occurrence date (by checking the frequency of the Scheduled Order) and update the status of the Scheduled Order to "Active".
  3. If the transaction was not completed and paid successfully in NMI, and you wish to retry processing the payment, you should wait at least 20 minutes from the time of the last processing attempt and then Continue Processing the Failed Scheduled Order.

  4. If the issue is persisting and you wish to work around it, NMI suggests that you can enable the option to "Include Order ID when performing Duplicate Transaction check" in the "Advanced Merchant Features" of the merchant setup in your NMI gateway.