On Backorder Status and Notification when Product Quantity is OK

[mallrat]

Hi Folks...

I have tried elsewhere in the forum, but I cant seem to get an answer and I think this is a bug.

Prestashop 1.7.3.4.

The store (which is currently offline) sells one off individual items. So the product quantity is usually just one or sometimes two items.

The problem is when the product quantity is set to 1, and this happens with every single order.

1. The customer adds 1 item to their cart and checks out in the normal way.
2. The customer receives the order confirmation email. (so far so good)
3. The customer also receives an email saying 'On Backorder' this order may be delayed. (not good)
4. In the back office the product quantity has gone down from 1 to 0 and the orders section shows the status as 'Payment accepted' but also 'On backorder (paid)'.

In the product settings in the back office, allow ordering of out-of-stock products is set to 'off'. I have tried switching this on but I get the same result.

Why is Prestashop setting the order status to 'On Backorder' and sending the backorder notification when the quantity available was enough for the order.

Thanks.