Moving file to folder in HD?

I'm trying to move a .mp3 automatically into a folder inside a exFat hard drive. I can move the file anywhere on my system except this exFat hard drive. This is how I set it up.
If "all" of the following conditions are met
"Extension" "is" ".mp3"
Do the following to the matched file or folder:
"Move" to folder "Extra Space"
The "Extra Space" is the name of the exFat hard drive. Any ideas? Thanks guys!
If "all" of the following conditions are met
"Extension" "is" ".mp3"
Do the following to the matched file or folder:
"Move" to folder "Extra Space"
The "Extra Space" is the name of the exFat hard drive. Any ideas? Thanks guys!