Delete Position Hierarchy in Oracle HRMS

The Lowermost position should be deleted first

DECLARE
   ln_ovn   NUMBER := 1;
   CURSOR c
   IS
      SELECT     LPAD (' ', 5 * LEVEL) || has.NAME HIERARCHY, LEVEL,
                 hap.NAME parent_name, pse.parent_position_id,
                 has.NAME child_name, pse.subordinate_position_id,
                 pse.pos_structure_element_id, pse.object_version_number
            FROM (SELECT NAME, position_id
                    FROM hr_all_positions_f_tl
                   WHERE LANGUAGE = USERENV ('LANG')) hap,
                 (SELECT NAME, position_id
                    FROM hr_all_positions_f_tl
                   WHERE LANGUAGE = USERENV ('LANG')) has,
                 per_pos_structure_elements pse
           WHERE pse.business_group_id = 141
             AND hap.position_id = pse.parent_position_id
             AND has.position_id = pse.subordinate_position_id
      --start with pse.parent_position_id =
      CONNECT BY PRIOR pse.subordinate_position_id = pse.parent_position_id
             AND PRIOR pse.pos_structure_version_id =
                                                  pse.pos_structure_version_id
             AND PRIOR pse.business_group_id = pse.business_group_id
        ORDER BY 2 DESC, 4;
BEGIN
   FOR i IN c
   LOOP
      BEGIN
         ln_ovn := i.object_version_number;
         hr_pos_hierarchy_ele_api.delete_pos_hierarchy_ele
                   (p_validate                      => FALSE,
                    p_pos_structure_element_id      => i.pos_structure_element_id,
                    p_object_version_number         => ln_ovn,
                    p_hr_installed                  => 'I'
                   );
      EXCEPTION
         WHEN OTHERS
         THEN
            NULL;
      END;
   END LOOP;
END;