A family of Microsoft word processing software products for creating web, email, and print documents.
It sounds like that section has been set to start on an even page.
Click on the page that should be 39. Then click the dialog launcher arrow in the bottom right corner of the Page Setup group on the Page Layout tab. In the dialog, click the Layout tab. If the "Section start" dropdown says "Even page", open the dropdown and select "Odd page".
By default, the Apply To box at the bottom of the dialog will say "This section". Since you want every section of the document to start on an odd page, you can change that to "Whole document". Then click OK.
Page numbers in headers and footers should change immediately. Page number fields in the body text (which are rarely used) will have to be updated by selecting the text and pressing F9, or by going to Print Preview.