Pathetic services

I bought a bed in february whuch had a year guarentee end of feb the bed sunk in the centre.thereafter it was given back to the factory and a new bed was given of the same make beginning of march and middle of april same situation then i was asked to upgrade my bed to a 8000 or 9000 bed where the hell should i get that money from? The consultant at the store was extremely rude and says that for r2500 that is the type of bed we get but not realising we paid money they never gave us the bed for free. Today my husband tried opening the bed to see what is wrong and god that make is pathetic wood used there is worse than fire wood and not even worth using it is not strong and looks as small as branches