"Download using cellular" doesn't work

[Cybiko]

So I've been having an issue with spotify for the past few months where after a period of time it will prompt me to download using cellular to download music. I have the option switched on in my settings and I have my cellular on as well, still it prompts me with the same message. I' getting really sick and tired of this, I've tried deleting old files and photos and apps Iim not using, I've tried deleting my cache and starting from scratch (same account, all my music deleted). 

Not really sure what' going on, I just really want to be able to have more music on my phone and if I'm paying for Premium I don' want horrible bugs like this. I would consider a different app but I have a Galaxy s8 and I can' get Apple music so idk. Pls send help.