Giselle 3 seater swing
Refusal to give refund

I purchased a 3 seater swing, as a GIFT. It turned out to be unsuitable for area. We did NOT open the box and I have the receipt, but was told " Harvey Norman do not sell goods, to give refunds, for whatever reason". I tried to explain the situation, but was rudely told, that is their policy and there would be no refund given. I phoned Head Office and spoke to lady there and she said she would ring the store and get them to phone me back. They didn't ring back, so I phoned this lady again and she said she would ring again and get them to ring me. Several days later, I did receive a phone call from the store manager. He said they would take the swing back, but there was a charge of $99.00 (20%) for cancellation fees. I think this is "highway robbery" and told him so. Do consumers have any rights here?
Please help me to get the FULL REFUND, I believe I am entitled to.