Sounds like you’re a victim of a scam......did somebody fill out a change of address form under your name?
As for reaching a person.....I’ve had no problem here.
Since the USPS is a federal entity....start by calling your Congressman or US Senators for help.
Most all mail gets through - it’s random things that get sent back... a rent check was ‘lost’... insurance papers returned, etc... I assume a scam would mean all my mail was being returned - - but it’s not.
It’s happened maybe 5 or 6 times in the last few months.
So, you get through to your post office... a national number? The one I googled had a phone tree that was impossible to use to get to a person. Maybe the number you have for your area of the country works... Mine doesn’t.
Anyhow I left a note for the mailman to knock... maybe he’s got some ideas.