3198458 - Business Partner relationships not replicated from SAP Cloud for Customer to SAP Marketing Cloud

When replicating business partner relationships from C4C to Marketing Cloud via iflow "Replicate Business Partner Relationship to SAP Marketing via Business Partner Web Services", you see that the iflow is completed in the SAP CPI message monitoring, but there is no successful record in the Marketing dashboard. The relationship is not updated in SAP Marketing cloud as not data was received from CPI.

C4C MARKETING CPI ROLES RELATIONSHIP ROUTER NOT EMPTY , KBA , CEC-MKT-INT-CSL , SAP Marketing Integration with Cloud Sales , LOD-CRM-INT-YMT , Integration of C4C with Marketing , Problem