Hi clarkaster1,
Thanks for taking the time to share your experience with Tuft & Needle … I appreciate it 
I don’t think that any reputable retailer or manufacturer would ever promise that a mattress would get rid of back pain so I’m not sure where you read this. The best a mattress can do is keep your spine and joints in good alignment which can help prevent back pain if your back is in good condition and can also help in the healing process if you have preexisting back issues (along with medical treatment or course) but a mattress that keeps one person in good alignment may not work nearly as well for someone else because each person is unique in their body type, weight distribution, sleeping positions, and physiology. The only reliable way to know whether any mattress is a good match for someone in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences) or how it will affect someone’'s back pain is based on their own personal testing or sleeping experience although firmer mattresses (but not too firm which can also cause back discomfort or pain) will generally have the highest odds of success for “most” people with back pain.
I’m not sure how long you’ve had your mattress but there will also be a break in and adjustment period for the first few weeks as you get used to a new sleeping surface (see post #3 here) so I’m looking forward to any ongoing feedback you have the chance to share.
Phoenix