Sealy Bed Grande ll

I bought a sealy grande ll at OK furniture in sasolburg on the 3rd of June 2025 cause I believed in the brand... but unfortunately im very much disappointed with quality of the mattress ... its not even a month and already the mattress caved in ..I have rotated the bed two twice cause its so uncomfortable...im really disappointed cause I cant have a peaceful sleep because of the bed ...in no time it will start to make noise...you can't even sit on top of the bed cause it will swallow you ... kindly assist.