Bad after sevice. The Worst ever

I purchase a bed for my spare room for my grand daughter in Nov 17. After the 1st time she and me { her weight 14kg mine 50kg) I realized this bed it not good at all. Called suppliers and customer care. After 1month they call informed me that they will send someone from Strandfoam "to come and inspect" only slept on it ones. I then waited till 7 thFeb 18. Informed me by email if my problem was resolved. Told them NO. They said they will follow up. I said please replace with a better one even prepared to paid in. NOTHING happened.