Won't download - Windows

[JMC043]

I use Spotify Player for a while now and some issue still is bothering me. The list My Music won't download from itself for offline circumstances, because whenever my Wi-Fi isn't there, some tracks are unavailable and become blacked out (title). Is there some setting what causes this or can I manually start the download? The free space on my laptop isn't a problem, I have 180 GB free space. You can see the attachment for additional information. I don't see any error code, only thing is "Can't play the current track". As you can see at the screen shot, it's not the case with every track, and also the previously added tracks have this issue.