Photoshop Organizer-Can't delete empty folders

As I suspected, you have some "missing files" in the folder.  Since, you want to delete the folder, I assume that you no longer want the photos in it (or have moved them to another folder).  In order to clean up the catalog and avoid other issues in the future, I suggest that you select the photos in the folder and delete them. I believe you will then be able to delete what will be an empty folder.

Can you give us a screenshot of what you are seeing and also tell us a little more about what you are trying to do and why.

One possibility may be that the folder is "in use" by another program, e.g. Windows File Explorer or the Mac equivalent, and therefore cannot be deleted.  BTW, what OS are you using?

I'm new to Organizer too so dumb question here (not you).  You do have "folders" selected along the top of your screen right?  That shows a list of all your folders down the left side of your screen?  Then "delete" isn't bold when you right click any of the folders?