Main Menu on Mobile

First off I love the theme. It’s exactly what I’ve been looking for. There are different things that I’m looking on how to “correct” and one of those is the main menu on mobile. If I have my iPad in landscape the whole menu is shown, which is what I want; however the drop-down sections do not work. For instance, say I try to press the arrow to view more under “About Us” it then actually goes to About Us instead of showing the drop-down. Is there some way I can fix this. Thanks.