Changing Requestor On Requisition Gives Message: JBO-27122 java.sql.SQLException: Invalid Column Index (Doc ID 2061448.1)

Exception Details.
oracle.apps.fnd.framework.OAException: oracle.jbo.SQLStmtException: JBO-27122: SQL error during statement preparation. Statement: SELECT * FROM (SELECT pec.full_name,
  pec.last_name,
  pec.first_name,
  pec.email_address,
  pec.employee_num,
  pec.location_id,
  null AS location_code,
  to_number(:1) AS inventory_organization_id,
  hr_general.get_work_phone(pec.employee_id) AS phone,
  hr_general.get_phone_number(pec.employee_id, 'WF') AS fax,
  t1.name AS hr_org,
  t2.name AS business_group,
  null AS address,
  papf.full_name AS supervisor_name,
  pec.employee_id AS requester_id
FROM per_employees_current_x pec,
  hr_all_organization_units_tl t1,
  hr_all_organization_units_tl t2,
  per_all_people_f papf
WHERE pec.location_id is null AND
  pec.business_group_id = :2 AND
  t1.organization_id = pec.organization_id AND
  t1.language = :3 AND
  t2.organization_id = pec.business_group_id AND
  t2.language = :4 AND
  papf.person_id(+) = pec.supervisor_id AND
  (trunc(sysdate) between trunc(nvl(papf.effective_start_date, sysdate)) and trunc(nvl(papf.effective_end_date, sysdate)))

UNION ALL

SELECT pec.full_name,
  pec.last_name,
  pec.first_name,
  pec.email_address,
  pec.employee_num,
  pec.location_id,
  hrlt.location_code,
  nvl(hrl.inventory_organization_id, :5) AS inventory_organization_id,
  hr_general.get_work_phone(pec.employee_id) AS phone,
  hr_general.get_phone_number(pec.employee_id, 'WF') AS fax,
  t1.name AS hr_org,
  t2.name AS business_group,
  PO_POAPPROVAL_INIT1.Get_Formatted_Address(hrl.location_id) AS address,
  papf.full_name AS supervisor_name,
  pec.employee_id AS requester_id
FROM per_employees_current_x pec,
  hr_locations_all hrl,
  hr_locations_all_tl hrlt,
  hr_all_organization_units_tl t1,
  hr_all_organization_units_tl t2,
  per_all_people_f papf
WHERE pec.location_id = hrl.location_id AND
  pec.business_group_id = :6 AND
  hrl.location_id = hrlt.location_id AND
  hrlt.language = :7 AND
  t1.organization_id = pec.organization_id AND
  t1.language = :8 AND
  t2.organization_id = pec.business_group_id AND
  t2.language = :9 AND
  papf.person_id(+) = pec.supervisor_id AND
  (trunc(sysdate) between trunc(nvl(papf.effective_start_date, sysdate)) and trunc(nvl(papf.effective_end_date, sysdate)))) QRSLT WHERE (( UPPER(FULL_NAME) like UPPER(:19) AND (FULL_NAME like :20 OR FULL_NAME like :21 OR FULL_NAME like :22 OR FULL_NAME like :23)))
.......................
## Detail 0 ##
java.sql.SQLException: Invalid column index

Error Stack:
## Detail 0 ## java.sql.SQLException: ORA-01407: cannot update ("PO"."PO_REQUISITION_LINES_ALL"."TO_PERSON_ID") to NULL ORA-06512: at line 1 at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:462)