Help!!!!!! I can't sync my playlist completely on my iphone4S

[TracyKushington]

I've been with spotify for a few months now and even have all my friendonto start using spotify. I have this issue where I can't sync all the songs on the playlist. It would stop syncing after a few songs and have a red exclamation mark next to it. What does the exclamation mark means? I tried to reboot my phone, plug it into my Mac, keep it on the charger, reinstall the app several times. My iPhone hasn't been jail broken and I would have excellent wifi but it still doesn't sync the songs. Please help because I really like this app but its nit worth paying $9.99 a month if I can't listen to it offline when majority of the time I am on the train. 

Thanks, Tracy (New York, NY)