Bad customer service

A month ago "talking of may" I personally bought a high blood pressure machine of R1199 at clicks mall of the south, sadly the machine isnt working anymore and when I open thinking its a battery, the is a rust and it is looking very bad, took it back to the store as I only keep coppies of appliances, I went with my copy of the slip, 1st thing they said before they even knew about the reason that brought me back was " the original slip is compulsory" they can not assist me with the copy, fine I then tell my story then now being accused of having to put the item that even has a glass that could show have I put it in water. The two of them called the manufacturing they then told them guarantee its 2years that doesn't cover the defect of the item, they state "manufacture" the item was in a room that was mybe hot and made the item sweat so its my fault they say. How am I suppose to feel with such service???