Poor Online Ordering sysytem

Iv just placed and Paid for an order online, then get a phone call that they out of Stock, and now have to wait for 3 working days to get the refund, firstly how do you charge people if there is not stock, its really not hard to implement systems to prevent this. For instance confirm the order with the store first then process the payment. Secondly if you charge a client for something and then don't deliver, the refund should be done immediately. And don't say you cant because places like Mr D and Uber Eats can. So im now down close on R200 and have to go without lunch today.