Credit Card Processing Module Quick Fix - Itransact Gateway

I have a registration module which processes credit card payments through the Itransact gateway, stores the information in a MySql database and emails a confirmation to the form's owner. Database and components are already set up should be working fine - the only issue is I get a "decline" message when I test. I need someone to review the module and fix any kink that is found (if any). If you know php this should be an easy, easy fix. I will provide access information after bid is awarded.