Bad customer service

I order Luella bag online yesterday evening and order was confirmed. Foschini realized they have made a mistake by listing the bag with the other bag on sale so today I am told the item is out if stock and my order will be canceled yet their App shows stock availability at 3 stores. Why must I be inconvenience because of the negligence of loading items that are not suppose to be on sale and I have to wait up to 10 days to be refunded