A refund will be rejected by Amazon when the amount or scope of the refund doesn't match what the original Amazon order can support. These are the three most common amount-related rejections.
If the Shopify refund total is greater than what Amazon originally captured for that line, Amazon refuses the refund. Common causes:
Each line item on Amazon can only be refunded once. If you (or a buyer-initiated A-to-z claim) has already refunded a line, a second Shopify-side refund on that same line will be rejected.
If the item is already showing as refunded in Seller Central, no further action is needed — it's already done on Amazon.
Amazon treats tax and shipping as separate, one-shot refundable buckets. If the original order's tax or shipping has already been refunded once on Amazon, a follow-up refund that includes tax or shipping again will be rejected.
On the Orders page, find the row with the Failed Refund status and click on Failed Refund. The Failed Refund dialog opens.
In the dialog:
Click Confirm to retry the refund.
