Managing duplicate transactions

The semi-integrated transactions API endpoints let you configure enhanced settings to manage duplicate transactions.

The following settings help prevent duplicate transactions when you integrate with Cloud EMV solution:

Check-field

The check-field lets you assign the value of another field—such as invoice or purchase-order—to help manage duplicate transactions. When you send a check-field request to the semi-integrated transaction API endpoint, the system checks for duplicate transactions using the check-field, transaction type, an Approved status, and the amount.

The check-field in the request checks for duplicate transactions before calling the cloud solution service to activate the payment terminal. If a duplicate is found, the API endpoint returns an HTTP 200 status code and includes the check-field-duplicate field with a value of true.

The check-field-mid field lets you query all terminals associated with a merchant identifier (MID).

The transaction-emv service checks for duplicate transactions by matching the last four digits of the card, the amount, an Approved status, and a time window of the past eight minutes.

OLS gateway duplicate module

The OLS gateway duplicate module checks for duplicate transactions using the last four digits of the card, a time window of the past five minutes, an Approved status, and whether the Include Invoice setting is enabled in the duplicate check query.

The OLS gateway duplicate module triggers a query when a payment terminal response returns a duplicate transaction with the check-field-duplicate field as true.

If duplicate check query is configured to return a success response (HTTP 200), Cloud EMV solution returns a “Transaction previously approved” message to the terminal when a duplicate transaction is found.