I am unable to get any local files on my computer to play or show up on my iPhone.  I feel like I have tried everything at this point.  I've followed all the instructions given to me and looked up many different solutions, none of which have helped. 

  I have the local file of a song on my computer and it shows up in my Spotify.  I will add it to a playlist (either with other songs or completely by itself).  Then I hit the "Download" button on the playlist for my computer.  When I go onto my phone, I see the playlist but it is missing the song.  Downloading the playlist again changed nothing. 

I am absolutely sure that my computer and phone are connected to the same internet.  I have also tried setting up a Hotspot on my phone and connecting my computer to it, but that doesn't help either.  When I play the song on my computer, and then use my phone and hit "Listen on this iPhone" it tells me that the song is not downloaded and then tells me that I can sync it by following the steps that haven't been working.

A few other things that I have tried are making sure that my Windows Firewall is off for Spotify.  This seemed to be the problem for some other people struggling with this, but it did nothing for me.  I also uninstalled the app and reinstalled it, but that accomplished nothing as well.  

I have absolutely no idea what I am doing wrong here, so if anybody has any ideas that I can try out, it would be much appreciated.