Woolworths refusing to refund for an order they canceled

I ordered a pair of shoes on the 14th of March. Woolworths deducted the amount and canceled the order on their side as they did not have stock. I was promised a refund which has not happened. I phoned them last week on the 19th of March and they said the refund takes 3-5 days yet we were well pass the 5 day mark. I was patient. I called them again yesterday and they said the refund should clear by the 25th. To date still no refund. I want to warn all consumers about Woolworths and their refusal to pay back my money. It has been 12 days since the cancelation and no refund.