Are you talking about catalogs or folders? Lightroom can only open one catalog at a time.
I have one folder and one catalogue but in Lightroom under folders it shows as
1: Dave Photos / Diskstation
2: Diskstation/ Dave Photos
When checking under Edit, Catalogue Settings, General Tab they both show as the same location. The more recent photos are in Dave Photos / Diskstation with everything else in the other. Its no doubt related to something I've done when setting up the external drive, but just cant sort it out.
You seem to be confusing catalogs and folders.
I don't know why you have the two folders shown in Lightroom's Folder Panel (that's where they are, right? you didn't specifically say that), but those are folders, and not catalogs. Then when you check Catalog Settings, this has nothing to do individual folders, this is catalog file location only.
Maybe you can show us a screen capture of what you are seeing. That would certainly help.
I would ask about this on Lightroomforums... there is an easy solution I think but one needs to be careful in executing the remedy and they know about it there.
Looks like one of your folders is named DavePhotos (no space between Dave and Photos) but the other is Dave Photos (space between Dave and Photos). If that is the case, that is why Lightroom sees them as two different folders. You need to move the photos from one folder to the other.