Sub-Menu doesn't work properly (mobile)

Hi all,

I'm currently facing issues on a site specifically on the mobile navigation. I have a sub-menu for a menu dropdown, but the sub-menu only drops down when you click the little arrow to the far right. Is there any way for it to drop down when you hit the 'menu' tab too? That way you don't have to just click the tiny arrow to drop down. Currently when you click that main navigation option, it just closes the entire navigation on mobile. Thanks as always!