Thank you for the replies. I want to clarify the pattern from my side, because I do not think all cases are necessarily caused by the same mechanism.
I have seen three related but slightly different situations.
The first was a Business buyer / FBA case. A Business buyer placed an order for an FBA SKU where I had only just sent the initial unit to the fulfilment centre the previous day. I contacted Seller Support and was told late dispatch would not affect my metric because it was FBA. When I later checked the transaction record, the payment was released 56 days after the order was placed. When I contacted Seller Support again, I was told they could not trace shipment history older than 90 days.
The second was also FBA. Three units of the same FBA SKU were reserved. I contacted Seller Support and was told there was no pending order, cancelled order, FC transfer, or removal order related to that SKU. Later, the three units reappeared in my FBA inventory.
The recent duplicate-order issue appears different. Most of the duplicate orders I have seen recently were from ordinary retail buyers, not Business buyers. Some were placed within one or two minutes of each other. Over the last few weeks, these pending duplicate orders seem to have become more frequent. Only one was from a Business buyer.
In one recent case, a buyer placed two orders for the same SKU.
One order cleared after around 30 minutes, while the second order remained pending. I noticed that the pending order appeared to be from the same buyer and for the same item, so I dispatched the cleared order as normal.
Two days later, the long-pending duplicate order also cleared.
I contacted the buyer to check whether they intended to place a second order. The buyer replied the confirming that the second order was accidental.
I asked the buyer to request cancellation from their side, but they did not reply. One day later, I cancelled the duplicate order myself.
The result was that the issue affected both my late dispatch metric and my cancellation metric, even though the delay and duplicate-order situation were created by the pending-order workflow rather than by normal seller handling.
So I am not claiming there is one single cause. It could be buyer double-click/retry behaviour, checkout rendering delay, payment verification, Business-buyer authorisation, or an order-state refresh issue.
The problem for sellers is that we cannot see which state applies.
From the seller side, we may see a pending order, reserved FBA stock, a duplicate same-buyer order, or a cleared order with the dispatch clock running. But we do not see the internal reason: payment verification, Business authorisation, buyer retry, system retry, stock reservation, or another internal workflow.
That is why “ignore pending orders” is not enough guidance in repeated cases.
It may be fine for an isolated pending order. But when the same buyer / same SKU / same quantity appears within minutes, or when FBA stock is reserved without a visible order trail, the seller still carries the operational consequence.
What I would like Amazon to clarify is:
1. Can duplicate same-buyer / same-SKU orders be caused by checkout retry, payment verification, or Business-buyer authorisation workflows?
2. If FBA units are reserved but Seller Support cannot see a pending order, cancelled order, FC transfer, or removal order, what internal state is holding those units?
3. If a buyer confirms through Buyer-Seller Messaging that a duplicate MFN order was accidental, but does not use the official cancellation button, is there any cancellation route that avoids seller metric impact?
4. How long should sellers retain evidence when transaction settlement, FBA shipment history, and order visibility may not remain traceable for the same length of time?
At the moment, the seller-facing system shows the consequence, but not enough of the order state to make a safe decision.