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.