When I send an Order Adjustment feed such as
<MessageType>OrderAdjustment</MessageType>
<Message>
<MessageID>1</MessageID>
<OrderAdjustment>
<AmazonOrderID>104-3121897-1466636</AmazonOrderID>
<AdjustedItem>
<AmazonOrderItemCode>42555034632370</AmazonOrderItemCode>
<MerchantAdjustmentItemID>6174012</MerchantAdjustmentItemID>
<AdjustmentReason>NoInventory</AdjustmentReason>
<ItemPriceAdjustments>
<Component>
<Type>Principal</Type>
<Amount currency="USD">0.15</Amount>
</Component>
<Component>
<Type>Shipping</Type>
<Amount currency="USD">0.50</Amount>
</Component>
<Component>
<Type>Tax</Type>
<Amount currency="USD">0.00</Amount>
</Component>
</ItemPriceAdjustments>
<QuantityCancelled>1</QuantityCancelled>
</AdjustedItem>
</OrderAdjustment>
</Message>
it reduces the monetary amount of the order by the amounts in the feed, but does not change the order quantity, so the order still shows the original number of items as needing shipment.
According to the documentation, including the QuantityCancelled with an AdjustmentReason of NoInventory will create a partial cancel, but this does not seem to work.
Is there any way to reduce the quantity of items on an order?