Download offline songs using mobile data doesn't work

[forzadamuse]

The title is obvious... When I used another mobile data provider (my friend's simcard) it worked, but when I used my own mobile data I usually use it didn't work. I've reinstalled the app couple times, I've turned it on in setting and in the playlist but still it won't download any. What is wrong actually? Is it my phone or the mobile provider? What should I do?