The customer used an Amazon-generated prepaid UPS return label to return an empty box, but the package is undeliverable due to an "incorrect or missing street address."
After talking with UPS, we were informed that the address on the UPS label was edited/altered, causing a address mismatch in their system. UPS was unable to deliver the return package in such circumstances.
In the meantime, the customer filed A-to-Z claim and received a full refund without our knowledge. We believe the decision may have been based solely on the fact that the package was dropped off, without awareness of this type of scam. The customer never intended to return the item to us.
I have filed a customer support case 17882911261 but have not got any useful reply yet. Could any Amazon moderator @Seller_FJwyF3iu5qxUY help on this issue?
I also found a previous post sharing the same type of scam:
https://sellercentral.amazon.com/seller-forums/discussions/t/ad8b8716-4b56-4320-a255-8f8de194a433