Somthing is wrong with my Sparten Ops.

I started to play halo 4 and I beat all the Missions of Invasion not by my self online with other players but when I go to go on the mission Expandables it wont let me play with other players on it? I don’t know how to fix it and I don’t want to play by my self I want a team to play with and it wont let me find a game for the mission Expandables so it would be really helpful to help me out. It says you can join Sparten Ops for the current Missions but theres more than just that Mission and I want to beat all of the missions because I haven’t been playing Halo 4 a lot lately and now I am and I can’t even play the Sparten Ops… So if someone can help me it would be highly appreciated! :slight_smile: