Animation is moving my object instead of deforming it

I made a bow with animation in 3DS Max and looks like this when acting correctly:

alt text

When I import it into unity however, instead of deforming and looking like the gif above, it moves the entire parts all together. As in, it doesnt pinch the string or curve the base of the bow, it takes the whole string and the whole bow and moves them. The kind of behaviour you’d get if each vertex had a weight of 1.

If your animation is based upon a deform applied in 3DS, it won’t work.
You have to use bones / skeletal animation.