Very Bad online store

I'm so ****ed right now, I purchased sneakers yesterday the 25th of October 2021. I got a confirmation email that my purchased was successful. Today on the 26th I get an email that the sneakers I bought are out of stock and they have processed the refund. Why is it out of stock but when I was bought it yesterday it was successful? I don't want refund I want the sneakers I bought. You're very unprofessional, don't put items knowing that you have the stock.