eng_eco_pub.Process_Eco() not assigning derived roles to workflow steps

We are creating Chagne Order in Oracle PIM using eng_eco_pub.Process_Eco(). The change order is created fine but all the derived roles are unassigned. The change order type has three statuses Open, Approval and Implemented. For Approval, we have defined a step which will be assigned to users having certain role,say item author, on the item. Process_Eco() is failing to assign this step to users which have item author role on the item. GUI shows unassigned.

This change order works perfectly fine when created manually through GUI. Hence I dont think any issue with configuration. Below is the code we are using: