Getting an error message about chat

[whoiamorwhoimnot]

I'm getting a wierd error about chat not working properly and the prefixes and the prefix colors do not show up.
[Server API] Warning Plugin "TShock" has had an unhandled exception thrown by one of its ServerChat handlers: System.FormatException: Index (zero based) must be greater than or equal to zero and less than the size of the argument list. at System.Text.StringBuilder.AppendFormatHelper(IFormatProvider provider, String format, ParamsArray args) at System.String.FormatHelper(IFormatProvider provider, String format, ParamsArray args) at System.String.Format(String format, Object[] args) at TShockAPI.TShock.OnChat(ServerChatEventArgs args) at TerrariaApi.Server.HandlerCollection'1.Invoke(ArgsType args) in D:\a\TShock\TShock\TerrariaServerAPI\TerrariaServerAPI\TerrariaApi.Server\HandlerCollection.cs:line 109

I modified the config.json but it did not work before I even touched it.

[Arthri]

What is the value of your config option ChatFormat and ChatAboveHeadsFormat?