Paint not sticking

Had an ICBC claim done to my car in 2003. Hood was repainted because of deep scratches.  Paint has blistered all over , Im being told its because there is to much osmosis in the hood itself and that paint will never stick to it.  Has anyone heard of this, and if this is true, other then buying a new hood as I have been told to do, what can be done to prep the hood so  the paint will adhere.