FND_SUBMIT API is not working

I am not able to submit the request set with the below sample code.

When I execute the code the request set is showing in fnd_concurrent_requests table with phase_code='P' and status_code='I'

But the stage is not submitting. So the execution is error out.

declare

V_REQUEST_SET_EXIST   BOOLEAN := FALSE;

req_id                INTEGER := 0;

l_CONC_PROG_SUBMIT    BOOLEAN := FALSE;

srs_failed            EXCEPTION;

submitprog_failed     EXCEPTION;

submitset_failed      EXCEPTION;

l_start_date          VARCHAR2(250);

BEGIN

fnd_global.APPS_INITIALIZE(user_id=>'27945',

                           resp_id=>'58936',

                           resp_appl_id=>702);

dbms_output.put_line('Calling set_request_set');