Unhappy customer

Good evening, Please be aware when you make purchases at Rochester, we bought a Kingsize bed from them about 1-2 months ago, paid cash as well. The mattress has sunk in the middle & we have been trying with no success to get them to pick up the bed & refund our money back. The Woodmead branch is where it was purchased from & the staff don't care one bit that this bed is not what was paid for. A 6weeks old baby has been sleeping on that mattress since birth & that is not good for her posture as she sleeps in the middle. You are my last resort in getting this issue resolved once & for all. Thank you