Local files downloaded on desktop app do not display on mobile spotify app

[zweavers]

I found a bunch of songs I liked but they were not on spotify so I downloaded them to itunes on my mac then put them on Spotify through the local files and onto my playlist and they worked fine, but when I try to listen to those songs on my iPhone it's as though they don't exist. I made a new playlist of just 6 "local files" songs to test it and when I looked at the playlist on my mobile it said there were 6 songs in the playlist but when I opened up the playlist it didn't have a single song in it. I have made sure my mac and iphone are on the same wifi, I turned on download for the playlists with the songs in it but it still will not work and I'm not sure why. It's getting really annoying and it seems like nobody else has this issue, am I missing something super simple? does anyone know how to fix this? any help is much appreciated!