InfoPath Dev

Hi Everyone. I have a form in a form library in sharepoint. There is a workflow set to run when a form in this library "is changed". When a user opens a form to work on it, they can save the form ONCE. However, if they continue to work on the form before closing, and try to save a SECOND time...

I have an InfoPath generated from a state machine workflow, the InfoPath is linked to a SharePoint list. The problem is: When I fill the fields of the InfoPath and click the Submit button (which submits the form and closes it), when I re-open the form I find all the data that I have just filled...