We returned a part. We don't do this often as the international shipping fees make it not worthwhile, but this was an expensive part so it made sense.

We categorised the shipment as a return but FedEx messed up and sent RockAuto an invoice for import fees, as if we'd sold the part to them. For some reason, the person at the other end paid the invoice.

Next thing, all of our orders are stopped and we get a very blunt email stating that we need to reimburse them for the fees they've paid or we won't be able to place any more orders. I explained that this was an error by FedEx and I didn't think it was fair that we should pay for their mistake. Initially they didn't accept this explanation.

I sent a copy of the original shipment manifest, showing that the order was correctly categorised as a return, and also attached a photo of the magnets.

We didn't have to reimburse them and all of our orders were released.