They do not have stock but allow customer to purchase items

I went online yesterday and bought a recliner and paid for it. I was called at around 15h00 and told that they just ran out of stock now. I kept on asking how is it possible that I could pay for it and then be told they are out of stock. The lady then owned up to the fact that the stock ran out last week and they did not keep their systems up to date. I then requested a refund as I refuse to deal with this company. I was told it will take at least 7 days. That is ridiculous as I paid and nobody gave me 7 days to fix my issues. Remember it is the COMPANIES issue. I am awaiting the response as I refused to accept the 7 day story. Earning interest on my money and not being able to supply the service. Shocking