query insertion rate need to increase

HI,

on 11.2.0.3 database.One procedire is calling some sql and it is doing bulk inserts.

Builk insert is happening through one package.

Below is the query inside procedure.Now It is taking 15 min for bulk insertion.

Now team want to reduce to 11min.Any idea let me know please.

CREATE
OR REPLACE PACKAGE BODY "PO_CALL_PKG"
/***************************************************************************/
/*
-- NAME po_call_pkg
-- TYPE stored pl/sql PACKAGE BODY
-- PURPOSE ...
--
-- HISTORY
-- MM/DD/YY Who Patch Description
--! 02/10/14 RG P324929_1 Modified to store trip charge information to
--! the call.
-- PROCEDURES
-- -----------------
-- create_trouble_call