issues playing certain artists on mobile

[Rhythmicc]

I've recently encountered a problem playing certain artists on my mobile device (Iphone 6s). This problem started in the last couple of days and I'm wondering if this is going to resolve itself, or I need to resolve it, or it will never be resolved. If this doesnt get resolved I'll probably not be using spotify premium anymore. 

I realize that spotify will sometimes make songs unavailable due to certain circumstances, however, I decided to buy the music that has become unavailable in order to add it to playlist on spofity. This has fixed the problem for the most part. Recently, I can only play certain artists on the desktop version of spotify. Songs that I used to play on my mobile device in playlist will no longer play on my phone but I can change the device and play the songs on the desktop from my phone. 

One instance of this is with: A thousand Times Repent - Curses another shape shifting wraith. When I try and play this song on my mobile device, nothing happens, but if I switch the device to my computer the song will play with no issue. I think this bands music was made unavailable in the past which prompted me to buy it, in which case i was again able to play it on mobile and desktop versions of spotify, this is no longer the case.