Apple Music not syncing songs added manually since iCloud library Sync turned off

I recently subscribed to Apple Music and started to sync my library but gave in as it was going to take too long due to amount of music, I therefore unsubscribed to Apple Music.

I turned off Sync Library and then tried to add a song manually to my Mac so that I can transfer it onto my phone. The song appears in Apple Music but when I select it to add to my phone it isn't there after syncing. I didn't have problems with syncing songs before I subscribed to Apple Music

I Dont want my music on the cloud as I have a NAS drive

How do I sync a song that I have added manually to the library now that I have Sync library turned off?