Duplicate K2 Infopath processes

I have a k2 workflow that uses an InfoPath form. The workflow has four events:

1. Submit Request

2. First Approval

3. Final Approval

4. Save Request form

After the user completes the first step I save the InfoPath form in the library. If the destination user uses the k2 worklist items to submit the InfoPath form it works correctly. However, if the user opens the InfoPath form from the SharePoint form library and submits it then I get two workflows: the one started when the form was initially submitted and the one started when one of the form is submitted from the form library.

Is there a way to just continue the workflow whether the form is submitted through the worklist or the form library?

thanks,

Luis