InfoPath Dev

I'm sure this is a very simple problem but I haven't been able to find any solution...

I have created a form and uploaded to sharepoint document library. After the form is submitted the status is changed to "submitted for approval" and an email is sent to a designate manager. My issue is, when that manager opens the form and approves/denies/edits anything and then closes the form, a new item is created instead of saving the edited version. There are three steps in the current process from start to finish and after the process has ended there are three items in the list. I only want one item in the list after it's been edited....can someone please tell me what I'm missing here? THank you in advance for any help.

You need to do this - http://claytoncobb.wordpress.com/2009/06/20/auto-generating-filenames-for-infopath-forms/

I pretty much use this method on all of my forms now.  Basically you will have a field that concats whatever you want the form to be named with a timestamp.  If that field is blank, it is filled in and submitted with that name.  If it is not blank (a form that was already submitted), the form in the library is overwritten.