Pathetic online service

I order some shakes on line on the 3rd and paid . Half my order arrived and the other didn’t . When I enquired about it they out of stock. Why does there system allow you to buy stuff and pay if they out of stock. Really bad service . They then sent an email if I. Want a refund in the account I bought from or my club card . This takes 2 days . I still haven’t got a refund two weeks later . This is really pathetic and unacceptable that they take your money and can’t delivery what you paid for . Even when you order they don’t give you a delivery date . You must just wait