Bad Service Nedbank Insurance

i bought a repossessed house two years ago which is financed by Nedbank and i took home owners cover insurance with Nedbank .Fast forward my wall collapsed last week due to bad weather and now Nedbank is refusing to rebuild my wall because they are saying the wall was not build properly. Worse part is the wall collapsed on my Neighbours car. I personally wouldn't advise anyone to take Nedbank insurance as they are always looking for a minor thing to reject claims