All offline music deleted on iOS

[JJ1982]

It is happening regularly that my offline music is deleted and I have to download it all again when I'm on wifi! It's very very annoying!! Your app is very unstable at the best of times but deleting songs is very frustrating!!

[Magnsmid]

It's probably your phone running out of space on the harddrive. This usually happens when ios try to make more space for updates or system critical files.

[JJ1982]

But I still have just under 40Gb of free space on my iPhone.....