Minus Stock Value

Hi Guys,

So I host an online store for my sister’s second hand clothes business – due to the nature of the business, there tends to only be one of each item for sale.

To launch this round of sales, she opened up the store for browsing 24 hours earlier, without the payment gateways open, to allow people to browse and add things to their cart, then at a set time turned on the payment gateways for people to check out – I believe it was a very busy opening, with around 50 orders in the first couple of minutes.

However – this seems to have caused a problem, with numerous items being oversold – where the stock was set to one and no backorders allowed, but multiple people have been able to place orders for the products, leaving the stock level at -1, -2 etc and in the worst case -4 stock, where apparently 5 of the product have been sold?

I searched and found something saying where concurrent orders are placed this has been noted to occur, but the post was a couple of years ago, so i’d assumed if it’s a bug something would have been fixed?

I did have Cloudflare running, the host (Ionos) provides this and it’s a one click set up sort of thing, so i’m not sure of the advanced level of specs behind this setup, and there is a speed/caching plugin set up, could either of these two be the culprit?

Thanks in advance
Ste

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