RH script: updateAll(true) does not add new file to TOC

I use this script to update my RoboHelp project from FrameMaker source before generating WebHelp:

var projectPath = "C:\\<path>\\<RH project>.xpj";

main();

function main()

{

        if(projectPath == "")

        {

               //Error!. Quit RoboHelp

               alert("Project path is not defined. \nPlease update the 'projectPath' variable in the script.");

               RoboHelp.quit();

        }

        RoboHelp.openProject(projectPath); // open the project

        RoboHelp.project.updateAll(true); // force-update FrameMaker source

          RoboHelp.closeProject(); // close the project

        RoboHelp.quit(); //quit RoboHelp

}

I added a new file to the FrameMaker book and it failed to add the new file to the TOC. When I ran the Force Update All command manually, it worked.

Do I need to add something or is that a bug?