the add section does not appear on pages

I'm using your theme and add to pages premiums and so far I'm very happy. But on the Web last I'm doing, I get the option not "Use sections" when I create the pages. I disabled the plugin and set again and nothing. There is nothing weird or different. A clean installation of wordpress in its latest version and its theme, to add premium and plugins I use regularly. In the other pages if you leave that option and is not. I can tell that this problem can occur.

Thank you