First, let's take a look at product alternatives:
Via your store settings, you can choose to use product alternatives automatically whenever a product from your store is out of stock. This allows for orders to still be fulfilled despite some items being out of stock.
Items that are used as alternatives are products from our catalog that have similar characteristics as the original you ordered. There may be slight variations but the alternative item’s build quality will be equal to or greater than the original product.
Product alternatives are free of extra charges. You won't be charged extra for the price difference between your product and the product alternative being used.
Visit our help center article for more information on product alternatives and how to activate them for your store.
You will be notified via email whenever one of your products is out of stock and an alternative has been used if you have enabled the setting to automatically accept the alternatives.
If you do not have product alternatives activated for your store, you can proceed with any of the following options:
You can cancel existing orders containing the OOS item via your dashboard.
If the OOS item is not the only item in your order, you can have the order short-shipped. This means the order will be fulfilled excluding the item that is out of stock.
At the same time, the listing variant that is related to the item that is OOS will be automatically disabled on your sales channel.