HDL giving error You cannot cancel this work relationship because the person has direct reports in a

Summary

HDL is throwing the error "You cannot cancel this work relationship because the person has direct reports in at least one assignment.", even though I have updated the supervisor of all his reportees

Content

When I view the person record, there is nothing in the Direct Reports section. I have run the programs Send Pending LDAP Requests, Autoprovision Roles for All Users, Retrieve Latest LDAP Changes, Import User and Role Application Security Data, Refresh Manager Hierarchy and Synchronize Person Records. Still, when I want to cancel the WorkRelationship using below HDL, I am getting the error "You cannot cancel this work relationship because the person has direct reports in at least one assignment."