Hi @Sean Sailor ,
The simplest way is to first add HR to the top link bar, and then drag it to turn it into a next-level menu.
- Click Edit Links on the Top Link Bar.

- Create new menu entries/links, by clicking New Link button.

- Once new links have been created, simply Drag and Drop menu links one under another.
- You can build multiple levels of menus using this technique.

- Don’t forget to hit Save once all set and done.
It worked for me:

For more information, please refer to:
https://sharepointmaven.com/4-ways-create-drop-navigation-sharepoint/
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