you can always try a safe-t claim and submit images of the box, label and item that was returned. If you win Amazon will cover you.

But, next time when you message them about a shipping error either let them return the order and have them ask for a replacement order.

That way you get the item back and they get the right item. You’ll just be out the shipping costs.

Or in your original message send your own prepaid return label purchased outside Amazon. That way the auto refund is not triggered on first scan.

It's not that you "trusted" the buyer but you didn't follow Amazon's system. Amazon has system in places for checks and balances and it's cumbersome but it reduces liability and shows a chain of actions. And that system is rigid, you can't just work around it thinking it will resolve in your favor. You shipped a product to the customer and a product came back, so amazon sees it at Payment to you and Payment to be returned. As a second shipment likely went out outside Amazon's control, they have no way to bill for it or match it up to an order and say this was an exchange

You shipped the wrong item and you owned up to it, that's great and you contacted the buyer and want to send out a replacement. "HOW" you send out the replacement is the next step you need to figure out.

1. Exchange - You inform the buyer that they can return a return and replace and Amazon will provide the return tag and once the carrier scans receipt, Amazon will post a new order and new shipping label for you to ship out. There isn't much incentive for a buyer to wait for the correct item to be received since they have to wait for the wrong to be delivered and then the right one to be delivered, so if we go this route we offer a monetary incentive if they choose this for our error.

2. Reship - You inform them of the error and that they can request to return the item and a label will be provided to them. To get the item quicker, they simply need to place a new order for the item, and a new order will be posted for you to process and ship. There is little incentive for them to place a new order since they're paying double and have to wait for a refund even though it's credit card and they don't actually pay anything right away (but then again some people have budgeting constraints), so in this we also offer monetary compensation "once the return" is complete.

If you shipped a shipment outside of Amazon's system for them to track the work flow it is an issue that you're asking a qualified individual to look over the transaction and Amazon isn't going to hire people for that, so they want it within their system. Now what's done is done and the only option for you to get paid is to contact the buyer and have them contact Amazon to have Amazon rebill them for the order. This is complicated and time consuming for the buyer and we can't imaging most buyers doing this unless they're honest people who want to do the right thing and do not want others to pay for a mistake, but a majority of people buying on Amazon aren't like that if you see all the people post about the free things they get from Amazon due to errors.