Appauling service

I bought a bed from Bradlows in February. In March I logged a complaint with the salesman that my bed is making a squeaky sound and needs to be replaced. In April a person from Sealy inspected my bed and authorised it to be changed. Since April I've been calling the store asking for a follow-up and nothing. Every person I speak to on the phone tells me they will call me back and never do. i also spoke to a lady at the head office by the name of Koei who assured me that my problem will be solved and still no results. It's been almost 7 months since I logged my complaint and no one from Bradlows including head office has bothered to give me feedback. I am the one who constantly follows-up. I am seriously considering returning the bed and demanding my money back. The bad service I received is disgusting.