Yes, that's what I was saying – I did turn it on, but it has not removed the space. Below is a screen capture of my settings so that you can see it is on:
The problem must be with your version then or with customization. So of you need to update theme files to latest version via FTP or you need to use the following css instead:
Comments
you forgot to remove Right Top Bar under Theme options > Header & Subheader > Extras section and that's why you got this empty space on mobile.
#Top_bar .top_bar_right { display: none !important; }