The one that really pissed me off was when Amazon would claim the USPS attempted delivery but could not and that I would have to call the USPS to arrange delivery. The carriers do this if they run out of clock. They just go back to the post office with a hundred or so packages at 5:00Pm and “too bad”. That is with 2 day delivery. Just try calling?!! They bring it eventually if they don’t steal it. Usually around 10 days later.
I found out that the USPS marks a package as delivered when it is loaded on the truck. I was tracking one and saw that it said delivered, but the mail had not arrived. When it did a short time later I mentioned this to the driver and he said they marked it package as delivered when it was loaded on the truck.
Another driver told me that letters marked “return to sender” just get dumped.
And after the USPS lost about $80.00 of auto parts from Amazon (who replaced them for free, and via Prime shipping), and after USPS would not answer the phone or disconnected me, when i finally got a veteran on the phone who confirmed they lost it, i called the Ntl. complaint number she gave me, which promised to get back to me soon. Still waiting about 4 years.