Sick and angry

I bought a Defy fridge on the 21st of Feb and i was told that they don't have stock but i could take the one that is on display . I only started using the fridge first week of March and i noticed that it was making a very strange sound ... I thought this would get better but it got worse and worse. The fridge is always ice on the top part . I went to the store Nd reported this ,i was very disappointed wen i was told that i wasn't gona be given another fridge instead they will send a technician to come and fix the fridge ..on the 28th of March the technician came and said the rubber on the doors was loose and assured me that the sound would stop and the top part will not freeze anymore . Hous3 and home called me back and i told them that i wasn't satisfied cos the sound was still there and the top part still freezes ... and i told them that i want this fridge to be exchanged the controller I was speaking told me that he cannot help me with that he will get someone in a higher position to call me back ... I haven't recieved the call , the freezer door now also has problems I have to use both hands to open the door this only started after the technician used glue on the rubber.... I am disabled ... i have scoliosis ( curved spine )this causes a lot of pain on my spine , i really hope that House and home will cover my medical bills while I wait for the new fridge . Actually I hope they will give me another brand cos even the controller did say they have a lot of complaints on the defy brand ...my question is why are they still selling it if they know it's problematic