made a fix myself. 

I am gussing its broken for me still because i use RustIO:Clans.

Here is the fix:

Step1: Look for the following code in the cs file-

        private string GetClan(BasePlayer player)
        {
            if (_isClansReborn || _isClansIo || Clans == null) return null;
            var clan = (string)Clans.Call("GetClanOf", player.UserIDString);
            if (clan == null) return null;
            var format = string.Format("[" + clan + "] ");
            return format;
        }

Step2: Now change this-

var format = string.Format("[" + clan + "] ");

to this-

var format = string.Format("");

Done :)