Amalgamated Bank They cashed a check that was stolen from me New York New York

Amalgamated Bank @ 275 7th Ave. NY NY 10001 cashed a hardship check I withdrew from my retirement fund from Prudential. The problem was I didn't cash it! It was stolen from the mail, a ups envelope delivered to the wrong address. The check was stolen in Newark NJ, my signature was forged as an endorsement to this mystery person and with no apparent security checks to speak of my check was cashed right there on the spot. $3,000 GONE! It's been a year now and I'm still fighting this stupid battle even though I have supporting documents, I even have the theirs account #. TRAGIC!!