Development Assistance help with command whitelist plugin

So, I am trying to make a plugin what makes plugins look like they are invalid if they do not appear in the config. It does compile and run without errors but the plugin does not show invalid command when i do /fly (not in the config).

Code:

public class Main extends JavaPlugin
  implements Listener
{
  FileConfiguration config;

  public void onEnable()
  {
    this.config = getConfig();
    this.config.addDefault("Commandslist", new String[] { "/plugins", "/essentials" });
    this.config.options().copyDefaults(true);
    saveConfig();
    getServer().getPluginManager().registerEvents(this, this);
  }

  @EventHandler
  public void onCommand(PlayerCommandPreprocessEvent e) {
    String cmd = e.getMessage();
    String msg = "§8[§c?§8] Unknown command. Please do §b/help§8 or contact a Staff Member for help.";
    for (String s : this.config.getStringList("Commandslist"))
      if (!(s.equalsIgnoreCase(cmd)) && !(e.getPlayer().hasPermission("commandhider.bypass"))) {
        e.setCancelled(true);
        e.getPlayer().sendMessage(msg);
        break;
      }
  }
}

Help and solutions will be much appreciated.