Ithala Bank Poorly built house

My mom bought a house in Port Shepstone a couple of years ago, and with in a few months it had major faults, foundation is sinking causing the house to have major cracks, she reported this way back in 2008 and nothing was done. A engineer came to evalaute this year again and found that its getting worse and its not only her house but other houses built in that area by the same company that Ithala Bank used. The report clearly states that the houses were poorly built hence the structural damage. Ithala Bank is doing nothing about, we have been lodging claims and they keep on dodging us.