In addition to the Errors applicable to all API endpoints, the following errors are specific to cancelling an order:

status code error code description
404 order.not-found No order was found meeting the requirements. Make sure to use the right orderId and API key. test objects can only be accessed using test keys and live object with live keys.
409 order.cannot-cancel The order has a status which doesn't allow cancellation. Only orders in requires_capture status can be cancelled
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