damage are not changing why ?

<?php

namespace ItemModifier\UnknownCod;

use pocketmine\event\entity\EntityDamageByEntityEvent;
use pocketmine\event\Listener;
use pocketmine\player\Player;
use pocketmine\plugin\PluginBase;

class ItemModifier extends PluginBase implements Listener
{
public function onHit(EntityDamageByEntityEvent $event)
{
$damager = $event->getDamager();
$target = $event->getEntity();
if($damager instanceof Player && $target instanceof Player){
$item = $damager->getInventory()->getItemInHand();
if($item->getId() == $this->getConfig()->get("Item1") && $item->getMeta() == $this->getConfig()->get("Meta1")){
$event->setBaseDamage(($this->getConfig()->get("damage1")));
}
elseif($item->getId() == $this->getConfig()->get("Item2") && $item->getMeta() == $this->getConfig()->get("Meta2")){
$event->setBaseDamage($this->getConfig()->get("damage2"));
}
elseif($item->getId() == $this->getConfig()->get("Item3") && $item->getMeta() == $this->getConfig()->get("Meta3")){
$event->setBaseDamage($this->getConfig()->get("damage3"));
}
elseif($item->getId() == $this->getConfig()->get("Item4") && $item->getMeta() == $this->getConfig()->get("Meta4")){
$event->setBaseDamage($this->getConfig()->get("damage4"));
}
elseif($item->getId() == $this->getConfig()->get("Item5") && $item->getMeta() == $this->getConfig()->get("Meta5")){
$event->setBaseDamage($this->getConfig()->get("damage5"));
}
}
}
}