I feel the pain of all of the above.
FBA a few years back was an absolutely outstanding reliable and trusted service. Recently it’s been an absolute joke, customers use and return brand new & factory sealed software with evidence of product keys registered. High value retail electronic products are returned many months after the purchase and amazon refund at will with no evidence presented by buyers (well against Consumer Rights Act 2015) and for sellers to bear the cost.
This year we have had 100% of returns either lost, damaged, or used and unselllable it its original condition. We have smart watches being retruned 5-6 months after purchase, with heavy use, chocolate bits on the back apparently as “faulty”, iPad keyboards returned with strawberry jam all over them, and simply products that have been heavily used because customer did not like the item.
That would be allright if we were selling low cost usb cables, and phone covers, but it’s extremely costly to 3rd party sellers when high value £200+ products are returned in such state. Appealing such cases - it’s extremely stressful, time consuming and most of the time absolutely fruitless.
We have now stopped using FBA and switched to SFP, FBM. It’s no longer worth the risk.