TV not working

I have purchase a Hisense TV 6 months ago... The TV was checked when leaving the store, and was delivered by them and not checked on delivery. Item was stored until I moved into new home. Upon Opening TV the whole screen was not working. I took the TV in, too branch in Rustenburg, According to there service department, they can not say that the TV was only used now, which I can understand but the plastic was still on the sides of the TV, and according to them it was mounted and it was definitely not. I requested them to replace the TV, and they refuse. Please help I paid R8000 for a TV which I cannot use at all.