Not sure when the last time you had to file a claim. Now they are filed at the claims division in St. Louis. Not at a local post office. On the claim form it give the St. Louis address.
Wish me good luck!
PS: When I was selling the small items like the snap caps, old bottle, etc that I imported from England, I lost so much stuff through USPS that I started to send the items through UPS and pay the min. one pound rate. Funny thing was that I never had a problem with the items being sent via post from England to here. Just when I was sending state to state.
Stay well
John Boyd