When an Amazon buyer asks to cancel an order, Amazon emails you and shows the request on the Manage Orders page in Seller Central. SKULabs also flags these orders so your team doesn't ship them by mistake.
How SKULabs shows buyer cancellation requests
During regular order sync, Amazon orders with a buyer cancellation request:
Get the Cancellation Requested tag.
Get an order note with the SKU being cancelled and the buyer's reason, for example "Buyer Requested Cancellation of SKU123: Found cheaper somewhere else", when Amazon sends a reason.
To make sure these orders can't be shipped, create a rule with the condition SKULabs order tag contains Cancellation Requested and the action Set order tag to a hold tag such as Hold - Cancel. See recommended tag names that alert your pickers and shippers.
How to handle the cancellation request
SKULabs doesn't accept or cancel Amazon cancellation requests for you. Decide what to do with each request in Amazon Seller Central.
The best strategy is to ask the customer to formally cancel the order under Your Orders on Amazon. Requests sent outside that flow are "unofficial cancellations" and count against your cancellation rate if you cancel them on behalf of the buyer.
Amazon says you can additionally send a "critical message":
"If the buyer doesn’t respond to your request in the buyer-seller messaging tool, you can send a critical message. Your email will be delivered to a buyer even if they have opted out of non-critical messages."