I run a server for a few of my friend. I'm thinking of making it public, but that's not important now. I installed a plugin called SimpleClans. I started up the server and checked it out. I ran into a problem where everyone had double prefixes. I created a clan and it went away for me. When I resigned from the clan my prefix stayed normal, but everyone else still had double prefixes. I removed the ChatManager.jar from PEX and instead used the essentials chat plugin. I tested it and people who had never been in a clan didn't have any problems, but for everyone else the prefixes were gone. It would be great if anyone could help. If you need any more information like my permissions file for example just ask.