cancellation of order

I purchased a microwave oven today on line at Makro. Followed all the procedures correctly. Confirmed delivery address and went into the cart and made the payment. Confirmed online that all was correct. 10 minutes later received another email with a cancellation and refund notice. Money will be refunded 7 to 14 days. 1. Why did the transaction go through when there is no stock (Takealot and Amazon block the transaction) 2. Why does it take 7 - 14 days to refund( Obviously they gain interest by keeping the money as long as possible) 3. Why does Makro not reply to any communication. LAST TIME I EVER BUY FROM MAKRO and I will warn as many people as I can to do the same.