Bad service and rude staff

On the 11th of July 2023,I purchased a gas heater from Pick ‘n Pay Sandridge square in midrand.the heater was faulty or rather programmed to switch off after an hour ,which it doesn’t make sense because the reason one buys a heater is to heat up the room or to be warm.on the 17th of July 2023 ,I decided to return the heater for possible exchange or refund.Which I was helped by very rude staff memebers who then tell me about the parkage .They didn’t agree to refund me they opted to replace the heater which the same scenario persisted in the antirum.Today I decided to return the heater with the original parkage box that is tone.I was told that I can’t get my refund as the box is tone.do I need to pay for the box or what?can someone please attend to this matter urgently as I am without my refund plus heaternin this cold.I am extremely disgusted by the service provided and the professionalism of the staff.