First, as to the sample document:

Why the .doc format?
I suspect file corruption, to which the .doc format is more prone.

Turn on display of non-printing formatting marks.Showing non-printing formatting marks in Microsoft Word

Go to the very end of your document and press the Enter key. That will produce an extra paragraph mark at the end. Copy the entire document into a new document except for that last paragraph mark.

Second,
I don't think "marge" is a word; if it is it is one with which I am unfamiliar.

You can find just about everything I know about Sections / Headers and Footers in Microsoft Word (Ribbon Versions) on that page. Pay special attention to Header/Footer Settings Recap. You cannot select the entire document and change the settings for multiple sections. It just does not work that way.

If the problem is messed up page numbering, there is a method to restart page numbering from page 1 and have it be continuous through multiple sections. It is implemented here: Continuous Page Numbering Add-In