DHL Delivered My Shipment Empty and Missing Items

My shipment with tracking number CB197967830DE, sent via DHL Cargo from Germany on August 15, reached Turkey on August 27 and was handed over to PTT. On September 9, I was contacted by Samsun Customs PTT and informed that the package was empty, containing only packaging materials. When I asked why it had been opened, I was told that every package passing through customs is opened and inspected. I requested an official report confirming that the contents were missing, but instead, I was given a signed and stamped document stating that the package only contained packaging and was exempt from customs. While the DHL online tracking system listed the shipment as weighing 3 kg, the PTT tracking system recorded it at 1400 g upon receipt. I believe the contents were lost during the transfer process. The package was never delivered to me by PTT, and I did not make any payment. I have official documents confirming that the package was empty. I request that the contents of my shipment be located, the responsible parties identified, and the necessary actions taken.