Horrible mattress

It sagged from the first day we got it. It was very different from my old mattress so I thought it was just taking some time to get used to it. I never felt refreshed upon waking. After a few months I started feeling pain in my back and hips. At first I thought it was some type of injury. I had some physical therapy which helped a little but when the therapy stopped the pain and tingling in my legs returned. I finally reached the point about six months ago that I wasn't sleeping through the night. I would wake up two to three times a night and try to find a comfortable position which was impossible. The sagging was getting much worse and I was in pain by the morning. I was so disgusted I went out and purchased another mattress even though this one was only 3 years old. Thankfully I am sleeping like a baby and wake up with no pain or fatigue.