Person DFF not validating in approval rules.

Hi

We are configuring an approval rule which will trigger when an employee changes addreess from ESS. The approval should be received by an application role configured in the rule. the rule configured is ((Current Person Address != Proposed Person Address) AND (Person.personDFFVA.unitHr.trim() == "Sky Tower")) The DFF introdced in he rule is configured in the person biographical information page. The rule is not picking the DFF and failing the rule. Ideally it should validate the DFF as well and pass the below rule in concurrent for smooth workflow. (Person.personDFFVA.unitHr.trim() == "Sky Tower") .

Please let us know if someone faced a fi.ilar issue.