CollectItem Method Missing

private void missing(CommandSender sender, String[] args)
    {
        if (!(sender instanceof Player))
        {
            sender.sendMessage(pl.PREFIX + "This is a player only command!");
        }
        else
        {

            if (PermissionManager.canPerform(sender, "collector.mod"))
            {
                String uuid;
                Player p = (Player) sender;

                Player otherp = null;

                if (args.length == 2)
                {
                    if (Bukkit.getPlayer(args[1]) == null)
                    {
                        sender.sendMessage(pl.PREFIX + "Zu wenig Argumente");
                    }
                    otherp = Bukkit.getPlayer(args[1]);
                    uuid = otherp.getUniqueId().toString();
                }
                else
                {
                    otherp = p;
                    uuid = p.getUniqueId().toString();

                }

                if (Main.mode == Vismode.time)
                {
                    sender.sendMessage(pl.PREFIX + "Nicht im Time Modus ausführbar");
                }
                else
                {
                    if (otherp.isOnline())
                    {
                        LinkedList<String> missingItemslist = new LinkedList<String>();

                        missingItemslist = pl.getMissing(uuid);

                        sendMessage(p, pl.PREFIX + ChatColor.WHITE + otherp.getName() + ChatColor.GOLD
                                + " hat folgende Items noch nicht gesammelt: ", ChatColor.GOLD);

                        for (int i = 0; i < missingItemslist.size(); i++)
                        {
                            sendMessage(p, pl.PREFIX + " - " + ChatColor.DARK_GRAY + missingItemslist.get(i),
                                    ChatColor.GOLD);
                        }
                    }
                    else
                    {
                        sender.sendMessage(pl.PREFIX +ChatColor.WHITE + otherp.getName() + ChatColor.RED +" ist nicht online");
                    }
                }

            }

        }
    }