Page Dropdown Menu Problem

Hi there,
I wonder if you can help…
Am just starting a new blog and some of my pages have sub-pages. In most themes, this comes out nicely as a top menu with a dropdown.
I just installed a theme called “Car One” which I like and I think I will use – but – the dropdowns are gone. They don’t seem to have any support that I can find, so I wonder if this is something you could help me resolve.
The site is here https://www.bodyworkplusltd.com and you can see the menu on top does’t drop down the sub-menus – but if you look in the right sidebar, you can see the pages & sub-pages there…
Any ideas what I could do? (Other than trying another theme)
cheers ?? paul