ZBrushCentral

Zsphere symetry problem

I am working on a dragon model and I am using zspheres but during the modeling my symmetry is of by several millimeters I can only scale one side while the other side is static, I am working on the dragon forelegs so I need that symmetry anyone knows how to fix that?
This is really frustrating I’ve tried to delete the spheres and create new ones but it’s the same problem one side static one good.