Photoshop Element 15 creating folders

[ElMicko123456]

I am creating new folder in Element 15.  When I it enter it shows in my folder list but when I click on it it disappears.  I then try to create a new folder and name it and it tells me the folder already exists.  Why is this happening? 

[MichelBParis]

The folders tree you are seeing on the left panel only shows by default the folders containing at least one image in the current catalog.

It's intended to manage the images in that catalog only without showing folders/subfolders not related to it, to keep a clean view. You can imagine that the displayed 'tree' is built only from the data in your catalog for clarity and efficiency. It's not subject to tree changes for unrelated folders outside the organizer application.

But...

You can decide to show all subfolders under a master folder by right clicking on that master folder and choosing the option to show all subfolders.