After change of position for an employee, the requisition in process doesn't go to the right approve

Hi,

We have a requisition  with status "IN Process".

We have an employee A to deactivate from the hierarchy and to replace with another employee B with the same position. So we remove the position for the employee A in Human Resources and add the same position to the employee B and we run "Fill Employee Hierarchy" program

The requisition doesn't go to the employee B and still going to the old employee

Thanks for your helps

Mohamed