Unsatisfactory service from Nissan

I purchased a Nissan NP200 from CMH Durban 3 years ago and the vehicle is still under warrantee but the company doesnt want to carry house repairs they are calling it wear and tear my vehicle has a 6 years warrantee and water is getting inside the lights if those lights were installed properly water should not be going into lights the company uses its warrantee for people to purchase vehicles but when issues like this come up they use every excuse to avoid the warantee