Adobe Acrobat Form

Hi all, 

I currently created a form in which one to three users use the form to fill a report. User one will fill the section belonging to them and the next user will do the same. To prevent any work done by the previous user from being deleted I have a submit button to flatten the pdf. There are no fields as the users just jot down notes. The issue here being that the button flatten with the rest of the page. Is it possible to protect a previous user's work without disabling the submit button.