Promotion fell through due to items being out of stock

On the 27th of November I bought 3 x 2 Pack bra's from Woolworths in different colours. This was on promotion, buy 2 get one free. Therefor I was only charged for 2 x 2 packs. On the 5th of December just before midnight I received a mail that my order is being processed with a note stating: "We're Afraid These Items Are Out Of Stock (You Won't Be Charged For Them)" This meant that I would be receiving only 2 x 2 packs and pay for both. The item that was suppose to get for free was not in stock. (So I wasnt charged for the item regardless.) I feel that this is unfair, as I now miss out on 1 x 2 pack I could have gotten for free. I saw this email today and immediately emailed and then called asking why they can't replace the 1 x 2 pack with a pack that they do have in stock. I was told that the order has already been shipped and cannot be changed. The lady informed me telephonically that their term and conditions state that Woolworths is not liable to fulfill the order if the items are not in stock. I am still trying to find these terms in their many terms and conditions. So I told the lady that I want to cancel the order, because I only bought the item because of the promotion. She said it is fine and she will make sure the parcel is not delivered and as soon as the stock is back with them I will be refunded. When I got home I saw that the parcel was delivered.

Woolworths could have contacted me with alternatives before shipping. This is a company I trusted to go the extra mile for their customers.