To assign or change the payroll entities for staff, follow the outlined path beow.
HR Plus ---> Payroll ---> Staff Pay Types ---> Click on "+Payroll Entity" ---> Select Branch ---> Click on the number of the Unassigned staff against a department ---> Select the Entity from dropdown ---> Click on Assign.
To edit the Payroll Entity, click on the number under Assigned Entities ---> Select the entity ---> Click on Update.