The correct filename would be -a-storage.mount. So try again with that.
I remember this is something I struggled with, as well. See:
https://unix.stackexchange.com/a/345518
Also see:
[root tip] [How To] Use systemd to mount ANY device)
and
An, to me, this: 
…doesn’t look right, as you can’t mount a disk, or “drive”. Only partitions ON a disk/“drive” can be mounted, and NVMe partition paths look like:
/dev/nvme0n1p1
Take a look here, it’ll help a lot:
2 Likes