Fails to honour guarantee 6 months down the line

I contracted Pinnacle Paint projects / waterproofing owner Tim Luis Des 2024 to fix the torch-on and repaint it with silver. R20k job that carries a 5 year warrantee. 6 months later the roof leaks. I phoned Tim Luis to arrange for him to go out. Since then he has been ignoring any calls on the matter and it is obvious that he is reneging on the guarantee.