the music dissepears from offlinemode

[lichemy]

why do the music I have downloaded to offline mode, dissepears on my phone and computer all the time? I have to download again and again all the time, and it's so irritating! So its not very usefull to have premium if the music dissepears from offlinemode all the time.. why does it happens?? 

its takes many hours to download again and again, and if I'm not home, it will cost very mutch to listen to the music...