USPS problems? Just a suggestion: Chain of Command.
It occurred to me many years ago most of us as employees report to someone, who in turn reports to someone, who reports to someone ...
I've had an issue with a couple of post offices. Asked the Postmaster for the name and phone number of the Regional Supervisor. Issue resolved instantly.
Friend of mine totaled a car in one of our lovely Minnesota blizzards and icy roads. Waited and waited for his insurance company to settle. I finally wrote a letter to the Minnesota Commissioner of Insurance. Couple of days later the friend came home to find the insurance agent waiting for him, check in hand, asking "Did you really have to get the Commissioner of Insurance involved?"
Same friend had an issue with Sears store in his area. VERY expensive Craftsman tool chest (he's an A&P Mechanic) failed; he returned it for full credit and purchased another - which quickly failed. When the store manager refused to accept the second, I went with the friend to confront the manager, who stated accepting the second would hit his "profit center" too hard. Next day I called the Area and Regional Managers for Sears. Tool chest was returned for credit; that (previous) store manager found himself working as a clerk in the hardware department of a different Sears store.
Couple of months ago a TV we purchased at Target with a "Square Trade" warranty went bad. Square Trade warranties are sold by Allstate - an insurance company. We had a repair estimate of $375; in a phone conversation a Square Trade representative offered $118. I told her we'd accept their check, but I'd refer it to the Minnesota Commissioner of Insurance - "you're an insurance company, after all." She put me on hold for a couple of minutes, came back to say they'd "make an exception" and mail a check to cover the full cost of a replacement - which they did.
Incidentally, I NEVER get loud or angry in these situations - it's simply business, NOT personal. The folk we're dealing with - like us - are just doing the best they can to get through the day, as a friend likes to say.
I can say from personal experience the LAST person a Postmaster wants to hear from is usually his or her Supervisor!
Dennis