This document will gives you overview about master data (ex:Controls) change workflow in GRC Process Controls
Central controls are created for sub processes under Business Processes
Once controls are created, if you open
If change master data workflow activated, SAVE button will disabled and Request change button will appear
First activate master data object for which you required workflow
SPRO>GRC>Shared master data settings>Activate Workflow for Master Data Changes
NOTE: Correct role selection is very important for business event and map with correct entity id, select notification business event if notification required.
Now go and change for control in NWBC, once you click on Request Change button, you get error
Reason: Not maintained user in fallback receiver
SPRO>GRC>General Settings>Workflow> Maintain Fallback Receiver
Provide details and click OK, will get the below message.
Hope it helps for others.