If your branch's stock also counts towards the available stock of your online shop, the available stock is checked as soon as you add an item to the cart at the POS. If the available stock is already negative due to online orders, or if the planned sale at the POS would result in overselling, a corresponding warning message is displayed.
At this point, you can decide whether to sell the item anyway or reserve it for open online orders.
If desired, you can disable this option via the plugin configuration.
Note: If your branch's stock is available exclusively for the branch and does not count towards the available stock of the online shop, no stock warning will be displayed accordingly.