Suspected duplicate transactions

In order to protect Helcim merchants against accidental duplicate transactions, the Helcim system has functionality built in that will automatically decline transactions that are potentially duplicates. This check was put in place to avoid accidental duplicate transactions processed through Helcim services, including the API and HelcimPay.js.

The suspected duplicates process is a secondary process to Idempotency Keys. This check will trigger even in instances where the flagged duplicate transaction has a different idempotency key from the original transaction.

The suspected duplicate check will review and decline any transactions where the cardNumber, cardholderName, and amount match a previous transaction within the last five minutes.

Suspected duplicate transactions will have a transaction status of "DECLINED" returned in the transaction response object, with an errors message stating "Transaction Declined: DECLINED - Suspected duplicate transaction in the last 5 minutes.".

// Example payment declined due to failing suspected duplicate check

{
	"transactionId": 21071575,
  "dateCreated": "2024-07-13 16:07:54",
  "cardBatchId": 0,
  "status": "DECLINED",
  "user": "Helcim System",
  "type": "purchase",
  "amount": 10.99,
  "currency": "USD",
  "avsResponse": "",
  "cvvResponse": "",
  "errors": "Transaction Declined: DECLINED - Suspected duplicate transaction in the last 5 minutes."
}