[Android] songs disappear and spotify stops out of nowhere

[Rosada]

Hi

I've been having some issues with my spotify. A few days ago, a lot of offline songs disappear. They're not available anymore. This happened with many other playlists. More than 1000 musics became unavailable.
I have enough free space to download these songs.
Today, as I cleaned my web history, spotify asked me to login into my account again. Ok, no problem. But after I did it, all my songs were unvailable. I tried to switch to microSD storage again, but it deleted almost 5 GB of music! Now I have only 25 MB storage.
Another issue I've been facing is that spotify stops playing out of nowhere. This really bothers me, because I have to stop what I was doing, force-shooting it and start all over again.
My smartphone is a LG Prime Plus 4G.
I really need to have theses offline songs available, because I don't have access to internet in my job. So I ask for your help to solve this.