Downloading music to device stops after 2-3 songs

[mrmann14]

On my iPhone 6S, when I try to download an album (make it available offline), it will download the first 2-3 songs, and then no more.  The only way to get it to download more songs, is to completly close the app and open it again, at which point it will only download the next 2-3 songs.  

I am doing this on Wifi, and storage space isn't an issue, as I have 18GB free. Anyone know what's up with this?