Item not appearing?

I'm so confused. When I add this item to a player's inventory, it adds it but its invisable until you relog. Can anyone help me with this?

Code:

package me.geetaff.CrafterCraft;
 
import org.bukkit.Material;
import org.bukkit.block.Sign;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.block.Action;
import org.bukkit.event.block.SignChangeEvent;
import org.bukkit.event.player.PlayerInteractEvent;
import org.bukkit.inventory.ItemStack;
 
public class SignListeners implements Listener
{
    //Wizard
    @EventHandler
    public void classSign(SignChangeEvent e)
    {
        if(e.getLine(0).equalsIgnoreCase("[class]"))
        {
            if(e.getLine(1).equalsIgnoreCase("wizard"))
            {
                e.setLine(0, "§4[Class]");
                e.setLine(1, "§cWizard");
            }
        }
    }
    @SuppressWarnings("deprecation")
    @EventHandler
    public void onClickWizard(PlayerInteractEvent e)
    {
        Player p = e.getPlayer();
 
        if(e.getAction() == Action.RIGHT_CLICK_BLOCK)
        {
            if(e.getClickedBlock().getState() instanceof Sign)
            {
                Sign s = (Sign) e.getClickedBlock().getState();
                if(s.getLine(0).equalsIgnoreCase("§4[Class]"))
                {
                    if(s.getLine(1).equalsIgnoreCase("§cWizard"))
                    {
                        ItemStack bob = new ItemStack(Material.BLAZE_ROD, 1);
                        p.getInventory().addItem(bob);
                        p.updateInventory();
                    }
                }
            }
        }
    }
}

 

GEETAFF hmm maybe try remove the p.updateinventory?

 

michael566 I already tried, same problem. I also found out it only updates if your hand is on the same slot as the slot that the item is getting added too