In mobile view with responsive site turned on clicking the menu button to open new options doesn’t work. I have searched high and low for a setting to fix this and I can’t find an option that looks like it is for the mobile menu.
have you enabled it in General Options > Header Options > Show Responsive Menu Dropdown? Please make sure it is set ON. If the issue persists, send us your wp credentials in a private reply. So we can give ti a closer look.