Well, complain to the post/seller.... That is not the result of a bump.
I think maybe you shouldn't have accepted the package.
I've seen a delivery UPS van going on a roundabout, it's back doors swung open, and there were packages all over the place. Fortunately, no traffic, no nothing was trampled by a car... but if it was fragile.. well.. it WAS. Also seen them throw stuff about. Gentle they are not.