Not a reliable dealer

Purchased a new arrival floor model mattress was advised the 10 yr warranty would still be valid. Well 5 yrs after spending $1700 on a Simmons Beauty Rest World Class 200 both sides of the bed are sagging and the middle has a large lump in it. I called about the warranty and was advised that on the invoice it was marked sold as is making the warranty invalid? Misleading information. I will never buy another product without doing research or reading the fine print on an invoice.