maya rigid binding question

breakneck

hey, i'm new to joints an all that. this is my first model i'm trying to rigid bind, and right now im working out the influences with the edit membership tool. howeverr i'm having some trouble now with the shoulder joint. it was working fine now i can't get any control point in both shoulders? anyone have an idea on what i could of done? clavical joint and elbow joints work. here are some screens:

clavical joint with edit membership tool active:


elbow joint with edit membership tool active:

shoulder joint with edit membership tool active:


?? all i need to do is pose this character so any quick fix would be awesome