Product categories don’t appear as option to build menu

I am trying to add my product categories as top level categories in the navigation bar on my site.

Under the “categories” option in appearance > menus, the only thing that appears under categories is “uncategorized”. My product categories do exist in the system as do products. What do I need to fix or change to be able to add them to the menu structure?

On the Menus page, click the Screen Options tab at top right. Then tick the boxes for products and product categories. That will make them available to be added to your menus.