Shoddy work and no effort to rectify

Cosmos Coatings water proofed the concrete roof above my garage in March. Unfortunately, the water proofing still lets water through and after numerous requests for them to rectify, I am only getting excuse after excuse. This is after I had paid them R8400 for the work done.<br> <br> The latest was that they were to come and fix the water proofing today (7 May). I have sent smses to them and they do not pick up the phone. What recourse do I have against them? <br>