Peach Payments

This error happens when a customer navigates back to the payment widget step after checkout, after entering their card details and progressing to the payment status step. The system does not recognise the session because there has already been an outcome.

A customer may do this if their browser disrupts the normal display of the transaction status, and therefore the customer is not aware that the transaction is successful. As such they click the "back" button on the browser to return to the order checkout step, to avoid having to go through the full checkout process again.

A checkoutID is created on every payment session. If a merchant's system queries the status of a transaction once (so that the system knows what to communicate to the customer and the administrator), the checkoutID expires and is no longer valid.

If you could share a date, amount, and customer name, we can try to investigate the reason why the transaction failed.

Possible  fix

• The copy and pay form tried to load without a checkout ID.
• If you are using the WordPress plugin, make sure you entered the correct API credentials.