I am so frustrated. Never buy a mattress at a furniture ...

I am so frustrated. Never buy a mattress at a furniture store!! Especially Marquis!!!
I spent almost 2,000 dollars on the mattress/box springs, adjustable frame and the salesman even talked me into a mattress cover .. ( helps extend your warranty , etc and protects mattress). First when my brother n law went to pick it up...they had sold my adjustable frame !! So I used it with the new mattress with the box spring which was ok. Finally I got the adjustable frame and together they are awful!!! I almost fall off the bed sometimes ...the edge is so low !!!😱
Also you can have the 4 support pieces in different heights and they gave me the highest one ... the shorter one would have been better .. they will not work with me whatsoever !! The manager told that once me once the mattress was in my house there are no exchanges. They are awful !!
She also said that I had tried it in the store so I should have known if I liked it!! Well...in the store it was on the box springs. Once you get the adjustable frame you cannot use the box spring !! So how was I to know that the mattress would be terrible when used with the adjustable frame !!!I bought there because I wanted to support the local businesses !! Most important thing I learned is to only buy your mattress from a mattress store !! Everyone that I talked to after this( at mattress stores ) said they would have let me exchange it. This is suppose to be my Golden years !! That's hard when I don't sleep well at night because of the mattress being so soft !! Kills your pressure points!!
Never go to Marquis !! They are heartless