Hi Mohan,

Please check if you have added the FW work class (XYZ- FW-CFW-work) in the inheritance of the implementation work class (ABC- DIV- Unit- work) and check the use-case again.

To add the FW inheritance work class, right-click on the implementation work class and select the definition. In the class inheritance class section, add the FW inheritance work class. 

After adding, just right click on the Implementation work class and click on inheritance to find the inheritance structure.

In addition to that please check the rule availability status of that particular section in the implementation class. If it is withdrawn  in the implementation then as per the rule resolution it checks according to the class hierarchy till the rule is found.