My landlord reported to the mail carrier I no longer lived at my current address anymore
Which was false. The post office stop delivery of my mail because of this. I put a report in with postal inspections along with the police dept. Prior to this incident I have put in several reports with postal inspections actually seeing my landlord stealing my mail. I have spoken to supervisors and managers at my local post office concerning these incidents. I have not received any help or justice concerning this matter from either agency. Can I sue any parties involved? What should I do?

Send a written report to the Post Master General in DC, along with a formal complaint about the local post office. Now, give a time limit to response before further action is taken.

ONce you have done this, contract the US Attoney General office in your area. It is a Federal crime to tamper with the mail.

In the meantime rent a box at the local post office so that you will be able to receive your mail without the landlord stealing it and throwing it away, or worse yet, looking through it. Be sure to put in a forward my mail to the post office box notice and speak with the postmaster who has your route about this problem and that you now have a post box for your mail.

I have never know just "telling" a postman would stop the mail, only a change of address can do that After 5 years in TN I was still getting mail sometimes for a person who lived there over 6 years ago.

IF you have proof of the landlord doing this, you may be able to sue the landlord. You most likely will not be able to sue the post office.