Bad service and poor quality bed

I bougĥght a bed from Sleep masters a year ago,I complained the 1st 3 months of receiving the bed.an inspector came to inspect and confirmed it was faulty and I received a new mattress,within a week the bed had the same sound as the 1st one,I complained again this time they delayed with feedback, I had to escalate to management, I was asked to send videos which h I did and was sent another mattress,I'm having the same sound again and don't know what to do,I did complain at the store but did not get any feedback, I'm frustrated and not happy with the service,I believe the quality of this bed is very poor,I paid off what I owed and that's what makes more angry,it's only been a year however the bed sounds like I bought it 5 years ago,please urgently look into my matter coz there is no sense of urgency from the branch and complaints department. ***