Technical Difficulties/Problems

I’m asking anyone who has encountered these problems or so, or at least can help me, Ive encountered a problem so whenever i attempt to load the campaign level “Forerunner” it says i don’t have the download-able content, and it stops on 17% of loading it.

My other problem is, Well, Maybe not really, But i played multiplayer before november, as i remember it.

Anyway, I heard you unlock more specializations by doing it, I haven’t got any except wetwork and operator.

Could anyone help me?

Seriously, Can i get any help?