EVOK furniture bed faulty on arrival, losing sleep

I bought an EVOK bed back in October. It was not properly made and makes a very bad creek sound when you sleep on it. I raised multiple support requests to get it fixed and they are playing me around since then. I am losing sleep as I am waking up multiple times in the middle of the night because of the sounds. this is seriously affecting my job performance and causing health problems ( I feel sleepless and tired the entire day). How do I make sure I either get them fix the bed or get them to refund the money.