Amazon throttles how many API calls can be made in a short window. If too many refunds are submitted in a short period — across all your orders combined — Amazon temporarily refuses additional refund calls and returns an "API throttle limit exceeded" error.

Why it happens

This is most likely if you:

• Issue many refunds in quick succession (e.g., bulk-refunding a batch of orders).
• Run other refund-heavy actions on the Amazon account at the same time.
• Have multiple users or stores hitting Amazon's refund API at once on the same seller account.

The throttle is temporary — Amazon resets the window after a short delay.

Fix it

Wait a few minutes and then retry. On the Orders page:

1. Find the row with the Failed Refund status and click on Failed Refund.
2. In the Failed Refund dialog, leave Refund Inventory, Refund Reason (Amazon), and Refund Amount as they are (they're already set from the previous attempt).
3. Click Confirm.