Transaction has been processed already

Error processing request: Transaction Error: Request rejected; the transaction has been processed already

This error occurs because the request sent to Unifi references a transaction that is either complete, errored or timed out. The reason for this is to prevent systems from spamming Unifi with repeat requests using the same ID.

If you are sending a receipt message, then this is likely to occur because the transaction in the receiving system is in an invalid state. Check the state of the receiving transaction, it should be in the awaiting receipt state, otherwise:

• If it is complete, then a previous request has completed it, and you must be sending duplicate receipts.

• If it is errored, then find out why and resolve. Your receipt will then process correctly.

• If it is timed out, then ensure you send the receipt in a timely fashion, or update the receiving systems integration settings to increase the time to wait for receiving receipt messages.