Sleep Number review: worn out in several spots hurts back worse than before

I purchased my bed 2 years ago and it is worn out in several places. i have tried replacing the foam from one side to the other it has completely worn out. when I purchase the bed it worked fine until i started loosing air. they replaced the side that was losing pressure. When purchased they said it had a lifetime warranty. this bed should be taken off the market it does what it say about a year (in which that's really when the warranty runs out) this bed has my back hurting worse than ever! you spend all of this money for the bed but, as soon as something goes wrong you have to spend hundreds of dollars to get it fixed! how can this problem be solved.