Dropdown menu items not showing on mobile

Hello! In my menu, I have a couple of headings which on desktop show dropdown items but on the mobile version, none of the dropdown menu items are displayed. Clicking on the heading doesn’t do anything. Please help! https://silchesterestate.org/

Hey there

This CSS code will reveal dropdown triangles, add it in the Appearance > Customize > Additional CSS:

.navbar-nav > li > .caret {
    display: block;
    color: black;