Mattress switched from what we bought

In showroom mattress was upgraded for 400 dollars extra on each. Purchased rize adjustable beds, king size but you get two single XL mattresses. Mattresses are showing depression in center and when you lay flat they make you lean to one side. Trying to use warranty that came with it, but I shouldn't have to its not the ones we purchased in the showroom. Yes I've been back to the showroom to try the mattresses we purchased and it's not what we got! Dealing with a guy named Dan from Heritage and he gives me a story of he knows what they did, mistakes my insides of the mattress with a less expensive one because they are similar. He also said they cut a king size mattress down to make the two single XL mattresses. Then I keep calling him and he says now he wants to come out and look. Total bs , nothing but the runaround. Should have kept my old bed. Hate when a company doesn't stand by their product, don't even know what to do. $2800 wasted on a crappy product, they switched mattresses!!!!!!!!