Offer goods at a price and cancel the order

After buying and paying for a welding machine and 2 other items, a week later Takealot just send me an email stating that my orders are cancelled, they where eager to accept my money now the orders which they had on offer at a reduced price which I paid is now cancelled and they still have my money, according to to my understanding, if goods are offered at a certain price and the price are paid, the goods must be delivered, **** way of doing business Takealot