Fulfilling orders and processing refunds with the Amazon sales channel
When a customer buys one of your products on Amazon, you'll receive notifications about their order from Amazon Seller Central and on the Overview page of the Amazon sales channel in your Shopify admin.
The inventory number that you allocated for that product when you created the listing in Shopify will update (but not your actual inventory level for that product in Shopify). You can log in to your Amazon Seller Central account to review the order details and manage billing and fulfillment.
Your orders on Amazon automatically sync up with your Shopify admin on the Orders page. All new orders placed through Amazon appear in your orders list and are marked as Amazon. The Amazon sales channel syncs all your orders, including orders for products that you didn't use the channel to list on Amazon.
You need to fulfill Amazon orders in your Shopify admin to update it in both Shopify and Amazon Seller Central. When you fulfill the order in Shopify, the order status is automatically marked as fulfilled on Amazon, with the same fulfillment date. When you're fulfilling Amazon orders in Shopify, make sure that you follow Amazon's Selling Policies, and mark orders as fulfilled in Shopify within Amazon's required timelines.
Your customers receive order notifications from Amazon only, and you receive notifications from both Amazon and Shopify.
At this time, you can't integrate Amazon sales channel orders with Fulfillment by Amazon. Instead, you need to manually fulfill orders in your Shopify admin.
If you need to refund an order from Amazon, then you need to process the refund in Shopify. A refund fails in Shopify when the order is already refunded in Amazon. If you refund the order in Shopify after you issued a refund in Amazon, then your reports might be incorrect. Orders refunded in Shopify will automatically sync to Amazon.
Because every order is linked with a payment in Amazon when you cancel an order in Shopify you need to provide a refund of more than $0. Learn more about processing refunds in Shopify.
Getting paid for orders
You can view payments from the Amazon sales channel in your Amazon Seller's Central in the Reports section. Learn more about getting paid at the Amazon Pay help center.