OPP manager pick first request only

Hello All,

DB : 12.1.0.2

EBS : 12.1.3

OS : Red Hat Enterprise Linux Server release 5.9 (Tikanga)

OPP manager only pick first request and after that next request is going in long running.

I found below in DB session

BEGIN

   fnd_cp_opp_req.postprocess (:reqid, :groupid, :flag, :errmsg);

END;

Wait event name ::    Streams AQ: waiting for messages in the queue

Bounce OPP, increase OPP profile option value , collected statistics but nothing works.