Amazon FBA Lost shipment- over 90 days

I have sent a shipment on 10th December 2021, its been delivered to amazon fulfillment center on 13th December 2021 by DPD (Tracking confirms that). Since then there is no update on the shipment, products never been received. I have contacted amazon about this countless times, I get the same response:
“Please refer to the target date in the reconcile section of your shipment summary for when your shipment will be eligible.”

Its been over 90 days now, the shipment has been closed, still they give me the same response. They have asked proof of delivery which I’ve provided and still I’m getting the same response

“Please refer to the target date in the reconcile section of your shipment summary for when your shipment will be eligible.”

I mean, there is no option to initiate any investigation, shipment closed, yet I dont get any update from amazon. Can anyone help?