WD My Passport (Mac) not recognised after OS upgrade

My Passport (for MAC) is new. Was installed 7 days ago and was working fine for backup. Last plugged in two days ago, unlocked using WD Drive Unlock application and backup successful. Drive ejected and left standing on same place in desk.
This morning I upgraded to OS 10.15.2.
Then plugged in the drive and tried to open using WD Drive Unlock.
The message returned says “You must run the WD Drive Unlock application from the WD Drive Unlock CD associated with the drive you want to unlock.”
I am assuming that something in the OS upgrade is the cause of the issue?
Any advice?

UPDATE: The problem must be caused by the Mac OS upgrade. I just installed the WD My Passport on another Macbook that has not yet been upgraded (it is running 10.15.1) and it all works perfectly.

I think this requires a resolution by WD?