Bad customer experience

We bought a bed last week from Rochester in Ballito, the bed got delivered only to realise as we were setting the bed up, that the mattress is too big. It was a surprise to us because we bought exactly what was in their showroom, which was a queen bed with a queen mattress. We then called Rochester the following day only to be told that we should return the mattress and take the right one. Now it’s a back and forth with them because we paid for delivery and they are the ones who delivered the wrong size mattress, but now it seems like they are making the problem ours. Now we stuck with a bed that we can’t use because the mattress is too big and taking the mattress back ourselves will cost us because we’ll have to pay to have the mattress taken back. It’s really disappointing and frustrating at the same time.