Marks Mattress Outlet Terre Haute Indiana review: Warranty the mattress and or foundation to fix the sagging problem that I have

I bought this mattress and foundation in 2019 it is still under warranty Marks Mattress will not honor warranty on mattress they sell they make phony claims that it is your bed that is to blame which is not the problem I have a bed that has 4 cross way supports they claim it shoud have front to back supports under the foundation which I also bought there