POiSON WORLD

Step 1) Find SID and Serial Number for Concurrent Job

SELECT a.request_id, d.sid, d.serial# ,d.osuser,
d.process , c.SPID ,d.inst_id
FROM apps.fnd_concurrent_requests a,
apps.fnd_concurrent_processes b,
gv$process c,
gv$session d
WHERE a.controlling_manager = b.concurrent_process_id
AND c.pid = b.oracle_process_id
AND b.session_id=d.audsid
AND a.request_id = 2063673
AND a.phase_code = 'R';

Step 2) Kill the long running session

--ALTER SYSTEM KILL SESSION 'SID, serial#' IMMEDIATE;
ALTER SYSTEM KILL SESSION '523, 4965' IMMEDIATE;

Step 3) Update fnd_concurrent_requests table to mark the request in error and completed

update fnd_concurrent_requests
set status_code='X', phase_code='C'
where request_id=2063673;

commit;

update fnd_concurrent_requests
set status_code='E', phase_code='C'
where request_id=2063673;

commit;

If this does not solve your problem then try restarting Standard Concurrent Manager and Output Post Processor Concurrent Manager.