Source IPSO to Nexus

This leg covers the failure scenarios in the submission of the pacs.008 by the Source IPSO to the Nexus Gateway.

The Source PSP must receive a technical acknowledgement (HTTP202) from Nexus to indicate a successful delivery of the payment to the Nexus Gateway. In the event the Source PSP does not receive this acknowledgement or receives a retry-able response (for example an HTTP429 - rate limit exceeded), the Source PSP should retry according to the Nexus retry mechanism.

Source IPSO investigation process

In the event the Source PSP has successfully sent the payment to Nexus but has not received a Payment Status Report (pacs.002), the Source PSP must initiate an investigation process. The Source PSP must send an Investigation Message (pacs.028).

Nexus will respond to the POST pacs.028 API with a Payment Status Report (pacs.002), containing the latest status of the transaction as known by Nexus. This can be used by the Source IPSO to complete its process. End-of-day, Nexus will also provide a camt.054 report containing the final and pending transactions.

The Source PSP must not unilaterally cancel the transaction. It must retrieve the final status of the transaction from Nexus.