Your situation only confirms that you should be very careful when shopping on the Internet for the time being. But that does not mean that they should not do it at all. The most important thing is to choose the online store carefully. All you need to do is to look at customer reviews. I don't think this situation would happen in a large store. Usually, they monitor the delivery of goods, and if there is any error, they will undoubtedly return the money. What is good about online stores is the ability to use promo codes for discounts. There are many services, such as this one https://www.dontpayfull.com/, which provide such an opportunity. Next time be more careful when choosing an online store, and this situation will not happen again.