URGENT HELP: Spotify will no longer send mp3 files to my iPhone

[djrobsd]

I can't get mp3 files to go to my iphone any more.  First, I download them from Beatport.  Then I move them to a folder on my mac that has been added to local files.  I usually create a playlist and add some of those files there, and select download so it's available offline.  I am running OSX 10.12.6 and Spotify version 1.0.67.582.g19436fa3. 

Iphone is on iOS 11.1

Now, I can see the playlist on my phone, but the files are not going there.  This seems to have started after getting the Iphone X, but I can not confirm for sure.   I have other playlists on my X that were working on my old iPhone 6 that have the local files on them, but now it doesn't want to copy any new ones.

This is critical and urgent.  I am a spin instructor, and much of my library comes from other sources like Beatport because a lot of the remixes to the songs are not available on Spotify.