Unprofessional online shopping

I'm disappointed in the manner in which my takealot order was carried out. I placed an order on the takealot app for a laptop which I bought for my son and was only told on the date of delivery that my order was cancelled due to supplier not having stock. The order was placed on the 26th and delivery on the 4th. This is very unprofessional of them because usually when they run out of stock it show's on their app that they don't have. Their refund policy takes more than 3 working days and this laptop is require at the school for his project. This has inconvenience me because I don't have the money on hand to get him a laptop which he wants. I called their customer service line and spoke to Ashley about my frustration but have not received any feedback. Why didn't you advise me on date I placed the order so that i can buy the laptop somewhere. Order number #***