problem

I agree with smidio. Most likely you have and independent head with head position strength not set to zero. An independent head by definition does not move the body.

You can do tricks like adding a second face behavior and head tag to the neck, with reduced strength. That can move the neck as if a head, which will move the chest etc too. Or just use a dragger for the chest.

You should get a little movement in the shoulders and upper body.

If the head is floating around, you might have an independent head that you havn't attached to the body? Hard to really help without seeing a screenshot or example though.