Lightroom Collections disappeared

Computer:  Mac

OS: Big Sur

Lightroom Classic 10.0

I recently moved files to a new external drive.  I've linked all of the files in their new locatons and all that is good.  The problem I have is that all of the "Collections" have disappeared  in the Collections tab.  All of the collections are still in the cloud.

How do I get all of the collections back into the computer?

Thanks for your help