Neto automatically assigns stock to multiple listings with the same SKU to ensure stock are not oversold on your sales channels.
A common issue clients experience is stock levels assigning itself to one listing and sending the other listing to 'out of stock' like in the example below.
Keep in mind the first listing will always take priority. To manage the stock levels evenly, simply go into your listing rules template, go to 'Categorisation & Listing Rules' Tab and scroll down to 'Stock Control'.
Adjust the 'Maximum Quantity to List*' to a lesser figure, save and revise all your listings for the SKU. This quantity will be the maximum amount of stock to allocate to a single listing before remaining stock is allocated to other listings.