If you're having problems with a particular order on an integration, feel free to contact our support team with your issue. Include the order ID so that we can resolve your issue faster. Here's how to find the order ID on Walmart and Shopify.
In Walmart Seller Central, go to Order Management and then Orders. Find the order you're having problems with. Copy only the Purchase Order # (the 13 digit number). The Order # is not necessary.
In Shopify, go to Orders and find the particular order that you're having problems with. In the URL, copy the 13 digit number directly after /orders/. Do not use the ID that is the header.