My Cloud not showing on Mac

Just bought a WD My cloud 4TB ext HDD, connected it to my network but my Mac is not showing it at all.
I was hoping it would be simple - that it would reveal itself, then I could drag stuff over to back up.
But it doesn’t seem to work that way.

Hi @GreyNomad500 ,

Have you opened a Support Case? If not opened, for more information, please contact the WD Technical Support team for the best assistance and troubleshooting:

No I haven’t because, as this is my first time on this forum, I imagined that other more experienced users might supply the answer. So I had better follow your advice - but solutions from other users still most welcome! Thanks. GN