
When I try to reboot, the desktop icons disappear, the reboot never finishes and I end up forcing a shutdown via the power button. resulted in "Unmount of disk2 failed: at least one volume could not be unmounted." which resulted in an error that it was already unmounted or "has a partitioning scheme so use 'disk util unmountDisk' instead"

which resulted in an error -69888: Couldn't unmount disk. Sudo diskutil eraseDisk JHFS+ Reformat /dev/disk2

Disk Utility failed to unmount the Data partition and reported the TM partition was OK, but I can't eject either without issues: Trying to reformat a drive that was used for an employee's Time Machine and Data storage.
