Parent folders not showing up in Lightroom Classic 13.5.1 on newly added SSD drive

I recently added a portable SSD drive to may Mac Studio (running OS 12.6.1 Monterrey). I created several categorized parent folders into which image files were then imported into their own subfolders. 

In the left folders column, the subfolders show but the parent folders do not. All of my other attached portable hard drives that do not have this problem.

Suggestions?

TIA,

John