FBX model lit strangely in unity

As you can see everything looks perfect in Maya :

But after I import the fbx file into Unity here's what happens:

(I choose 'Calculate' in the normals field in unity export settings to fix another weird problem with faces (black and white spots on object))

Red vectors show the bright side which as you see is in the wrong side.

And the other weird thing is that the right hand work perfectly and also it's a bit darker with every materials! The problem is the left hand.

Any solutions please?