Problème pour récupérer le joueur

package fr.zitugi.antikikoo;

import org.bukkit.Bukkit;
import org.bukkit.command.Command;
import org.bukkit.command.CommandExecutor;
import org.bukkit.command.CommandSender;
import org.bukkit.entity.Player;

public class MuteCommand implements CommandExecutor {

    @Override
    public boolean onCommand(CommandSender sender, Command cmd, String msg, String[] args) {

        if(sender instanceof Player){
            if(cmd.getName().equalsIgnoreCase("mute")){
                if(args.length != 1){
                    sender.sendMessage("§cSyntaxe : /mute <Player>");
                }
                else{
                    Player target = Bukkit.getServer().getPlayer(args[1]);
                    Mute.getInstance().setMute(target, sender.getName());
                }
            }
        }

        return false;
    }

}