Inferior bed

Bought a bed last year late the bed is just about a year old but seems as if its a century old the springs have popped out and the matress is coming apart, the bed is uncomfortable although it has 5 yrs warranty a sales agent from restonic says they cannot replace the mattress which is of inferior quality only because there is a stain on the matress so I take it the stain ruined the springs quality. Im am.highly unsatisfied with the service and of this , I am never going to purchase a restonic bed ever again.