Poor service

Standard Bank financed my house. The house was built from the ground up. Standard Bank sent an inspector to inspect the house to see if it meets the required standards, and the house was certified as fit to be occupied. I recently had a water pipe leak, and I contacted Standard Bank Insurance for assistance. They sent a plumber who came and identified the leaking pipe, which the rats had completely eaten away. He reported the issue back to the insurance. The insurance never contacted me back with the feedback or a way forward. I phoned them after five days, and they told me that they do not cover plastic pipes, only cover galvanized or copper pipes. How can they not cover for the same pipes that they approved when they built the house? I find this very disturbing, and as one of the tricks to **** clients' money. Some of the pipes are running in the wall; if one of them leaks, they dig up the wall to expose the pipes and then tell me that they don't cover plastic pipes. The whole house uses plastic pipes for plumbing. I don't know if I can continue to be a member of this insurance. I am really disappointed.