Event simply not working

Hello. I have the following code:

Code:java

@EventHandler
    public void onUse(PlayerInteractEntityEvent event) {
        if(Main.shadow.contains(event.getPlayer().getUniqueId())) {
            Player shadow = event.getPlayer();
            Player target = (Player) event.getRightClicked();
            if (shadow.getLevel() == 100) {
                Bukkit.getScheduler().scheduleSyncRepeatingTask(core, new Runnable() {
                public void run() {
                    shadow.sendMessage(ChatColor.BOLD + "" + ChatColor.GREEN + "Your STUN skill is ready");
                    shadow.sendMessage(ChatColor.BOLD + "" + ChatColor.BLUE + "Right click" + ChatColor.GREEN + "any player to use it.");
                    }
                }, 80, 80);
 
                if (shadow.getInventory().getItemInHand() != null) {
                    if (shadow.getInventory().getItemInHand().getItemMeta() != null) {
                        if (shadow.getItemInHand().getItemMeta().getDisplayName() == ChatColor.BLUE + "Shadow Sword") {
                            Main.stuned.add(target.getUniqueId());
                            target.addPotionEffect(new PotionEffect(PotionEffectType.BLINDNESS, 60, 1));
                            target.addPotionEffect(new PotionEffect(PotionEffectType.CONFUSION, 60, 1));
 
                            Bukkit.getScheduler().scheduleSyncDelayedTask(core, new Runnable() {
                                  public void run() {
                                    Main.stuned.remove(target.getUniqueId());
 
                                  }
                                }, 20L*4L);
                        }
                    }
                }
            }
        }
    }
 

And it simply does not work when having this exact sword or the 100 xp levels.
What is incorrect here?

 

(facepalm)
No I didn't

@timtower
So, what works:

- When I have 100XP it sends me the messages, but send it like 4-5 times with different delays, but with 101 levels it also works, not supposed to happen. Still I could not manage to give the blindness and nausea effects to the right clicked.

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

It is repeating because you told it to repeat. If you only want it to run once, use Delayed tasks.

 

I want it to be repeated every 4 seconds if the player has 100 levels of xp. I want it to repeat, but it's kinda bizzare the delays and spams it's doing, not every 4 seconds as supposed to.