Problem in sending RNIF Receipt ACK on Invoice Response

I am having issues when sending out Receipt ACK after receiving (and processing correctly) the Invoice Response.

The process model is receiving the Invoice Response document correctly and it is recorded and recognized as a TN document. Sender is my trading partner and we are the Receiver.

The problem is with the structure of Receipt ACK, we are sending out in the Service Header:
Buyer
Buyer Service

Seller
Seller Service

But partner is expecting this reversed. How do I set this up to reverse thse values?

In your TPA, try to change the value of:
ProcessInfo/SenderFocalRole
ProcessInfo/ReceiverFocalRole