update employee using API

Dear All,

im trying to update an employee using the API but unfortunately i got the below error:

"

SQL> Execute XX_update_empdata_api(0);
ORA-20001: The primary key specified is invalid

Cause:        The primary key
values specified are invalid and do not exist in the schema. 

Action:
Check the primary key values before attempting to carry out the operation again.

PL/SQL procedure successfully completed.

"

the code:

"

Create or replace PROCEDURE  XX_update_empdata_api (nb in number) IS

-- Local Variables

-- -----------------------

ln_object_version_number PER_ALL_PEOPLE_F.OBJECT_VERSION_NUMBER%TYPE  := 7;

lc_dt_ud_mode VARCHAR2(100) := NULL;