Can't play anything

[StepTNT]

So, I downloaded a lot of music for offline access (more than 2GB) and it always worked fine, but in the last two months I've not been able to play anything, not even the offline files.

Basically what happens is that my playlist looks empty, then I get a message saying that I don't have any favourite track and finally, once the tracklist loads, it gets stuck in a "loading" loop and there's no way to play any track.
If I'm able to press the play button between those infinite loading screens, it just stays still at 0.00 and it keeps on reloading until it eventually goes back to the step in which the tracks are missing.

Since my subscription will run out the next month, I need to know if we can make this work or if I need to look elsewhere.