FAULTY Sealy Posturepedic Belgro mattress

Paid for a King size Belgro mattress and base. The one side of the mattress collapsed within the the 1st 3 weeks after delivery. I reported it I was told to rotate the mattress once a week which we did with no difference. I reported it again and an inspector came out to report there is no default, no report given I had to ask for an email. I was told to rotate the mattress again which was done with no result. Both sides of the bed has has now collapsed and we have major discomfort. Between Mattress factory and Bravo brands they take no responsibility and don't even follow up. I need assistance to solve this matter urgently.