Sign into your account at https://sellercentral.amazon.com. If a buyer has requested that you cancel their order, you can do so from your Orders panel without it counting against your metrics.
If you have already shipped the order to the buyer, let the buyer know that the item is on its way, and that they should reject the package once it arrives.
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Click the Orders drop-down menu. A menu will expand.
Click Manage Orders. A list of your recent orders will appear.
Click Cancel order next to the requested order. You'll find it in the "Action" column next to the order.
Select a reason for cancellation. Choose the reason that comes closest to why the buyer requested a cancellation
Click Submit. Both you and the buyer will receive confirmation messages about the cancellation.
