Bad customer service

I bought my bed on the 25th of March 2024 @ Woodmead Retail Park, I reported that my bed has sunken on the one side of the bed on the 8th of November. I was advised to send pictures of the bed with a broom on top which I did and when I followed up on the feedback that's when tables turned. I got a call from Ernest(Manager) who was very rude and utterly disrespectful. He spoke to me in a tone that very condescending and when I addressed him about it that's then conversation went south. He asked if my bed was clean, and I told him yes as they also have pictures of my bed. I was advised that the bed has a 2-year guarantee and a 10-year warrantee. when I asked about a refund I was told he will not do that. The only way he can help me was for me to do a top up on a 'better quality bed' The original price of this bed was R6499 and I bought it on special at R4999, at no point was I told that the bed I bought was not fit for everyday use apparently the bed they sold me was for a spare bedroom use. I asked him why would I buy a bed for that I wouldn’t use everyday? I must say I am not impressed with the way Ernest handled him himself when he was speaking to me over the phone absolutely disgusting behavior for a manager.