ZERO APPLIANCE GAS FRIDGE

My daughter brought me a Zero Appliance Fridge/Freezer for my birthday in March 2015. Ok delivered the fridge and we installed it as indicated on the farm. We connected 19kg gas and was only doing 20 days before its empty. In June we connect a 49kg gas bottle and it only last 6 weeks. I contacted Zero Appliance and they said we must buy a new burner and thermostat and return the fridge to them on our cost for the installation. Which we don't have the money. Then we decided we will wait until Eskom install the electricity. We got electricity in December and we connect it to the electricity. The fridge was running for 5 days without freezing in the freezer compartment. First OK Furniture didn't indicate that we have to pay additional for thermostats, 2nd how could Zero Appliance sell electronics and not working properly. I want a refund from OK - Furniture or a gas stove in exchange for the money spend so far on the fridge. I was force to buy a new electric fridge because we can't loose all the food again that was supposed to freeze , and we can't loose the money that we have paid already on the fridge