Delete Emails Doveadm

Hi guys,

An email address today got hit with over 50,000 emails from Mail Delivery System as they got hacked and the hackers tried sending thousands of spam emails.

Currently trying to delete all those Mail Delivery System emails in cPanel, but I think I'm doing the Doveadm commands wrong.

I'm trying

doveadm search Subject Mail Delivery System

However I'm getting a Command #0 failed. It reported the following error: “/usr/bin/doveadm” reported error code “75” when it ended: Fatal: Unknown argument DOVEADM

Can something help point out where I'm going wrong.