Locale music from my PC won't be downloaded to my phone.

[the_butcher]

Hi everybody,

on my PC i have added some lokale mp3s to Spotify. After that i moved them into a playlist, then i connected my phone to the WLAN and started the Spotify App. After pressing the "download button" the download of the Spotify songs starts, but the local songs from my PC will not be downloaded, however they are at least listed.
Does somebody know what the problem could be?

Kind regards