Received false complaint; legal notices ignored — what steps next legally?

I received a show cause notice from my higher authority, which I responded to on time. Later, I obtained a copy of a complaint signed by 19 people, which was the basis for the notice. There are major inconsistencies between the complaint and the notice. I believe they conspired against me. I sent legal notices to each of them, but some refused to accept them, some didn’t reply, and some responded vaguely. One person who didn’t accept the notice still signed the group response. What should I do next?