Bad service and wrong advertising

We bought a headboard and bed in December and it was their demo product. We lay byied it. For 6 months to be on the safe side. Now when my wife is about to do the final payment they said the bed is not there and we lay byied it at the wrong price only now they tell us and they say we will get delivery in 14 days. When we say we want a refund they giving us stories about bank statement whilst we where paying in store. 1stly they move stores without telling the customers and the service at the branch in Centurion is really poor now we want our bed because we have already done the last payment. It's either they get us our bed between now and Wednesday or give us our money back simple