my passport for mac is not showing up as available in time machine

I confirmed in Diskpart that Automatic mounting of new volumes is enabled.All other USB drives and sticks I own do NOT exhibit this behavior.The problematic drive works fine when connecting to my Mac.I have another 4TB Western Digital My Passport Ultra drive (formatted in Fat32), that does NOT exhibit this behavior.Once reboot is complete all the 'Local Disks' created during this process are removed and the drive letters are once again available for assignment. In order to reclaim the drive letters I have to reboot (after disabling fast startup in power options, so hardware is re-initialized during reboot).Of course each time I have less and less drive letters available to me since the assigned letters never release. I can reassign another drive letter as I did in step 3 above and the issue repeats over and over.If I reconnect the drive once again a drive letter is not assigned (original drive letter remains listed as 'Local Disk' and is inaccessible).If I disconnect the drive, the drive letter remains visible in explorer and changes to 'Local Disk'.

I can now access the drive via file explorer and read and write files.

I right click on the drive and assign a drive letter which works as expected.Disk Management reports the drive as a Healthy Active Primary partition.

When I connect the drive the Disk Management application sees the drive but no Driver letter is assigned.

I have formatted the drive in Fat32 (Required for my device). I just purchased a new Western Digital My Passport 2 TB USB drive.

My passport for mac is not showing up as available in time machine