Can't change drive letter for DVD writer

Hi all! In Windows Explorer, the DVD RW drive appears as "E".
I want it to be "Z". Normally this is easily changed in "Disk Management".

But when I open Computer Management > Disk Management, I do not see the DVD RW drive.
Just to clarify this is a physical disk (no virtual drive).

I know I have seen it previousl in Disk Management, and changed the letter there, so I am not sure what the problem is now.
All other disks appear as expected -these are all SATA hard drives.

Any ideas?

I've seen time that an optical drive was not recognized unless there was a disc in the drive. Try it with a disc in the drive.

Yes, you are right! That worked...