Proof of Ownership Rejected for Lost FBA Shipment

Has anyone else run into this? CASE ID 15924089141

I recently sent an FBA shipment using Amazon's UPS partner program to the fulfillment center RDU4, but it appears to have gone missing. After 2 years of selling on Amazon, I’ve seen this happen occasionally, and it's usually resolved without much trouble.

I opened a case and provided proof of ownership for the lost items. Surprisingly, my claim was denied. I’ve used the same kind of documentation before without any issues. Yet, support won’t clarify why the documents aren’t acceptable—they only state that "the documentation provided doesn't meet one or more of the requirements for acceptance."

Amazon has acknowledged the inventory was lost, and I’ve provided all the required paperwork. But I’m still getting vague responses, and there’s no resolution in sight. Am I missing something here?