this is my code :: PHP: <?phpnamespace oi;use pocketmine\Player;use pocketmine\plugin\PluginBase;use pocketmine\entity\Effect;use pocketmine\level\particle\PortalParticle;use pocketmine\command\CommandSender;use pocketmine\event\Listener;use pocketmine\utils\TextFormat as Color;use pocketmine\command\Command;use pocketmine\math\Vector3;use pocketmine\item\Item;class main extends PluginBase implements Listener { public function onEnable() { $this->getLogger()->info(Color::GREEN."on!"); } public function onCommand(CommandSender $sender,Command $cmd,$label,array $args) { if($sender instanceof Player) { if((strtolower($cmd->getName()) == "oi") && isset($args[0])) { $player = $this->getServer()->getPlayer($args[0]); if($player instanceof Player){ $level = $player->getLevel(); $level->setBlock(new Vector3($player->x, $player->y, $player->z),Block::get(42,0)); $level->setBlock(new Vector3($player->x, $player->y + 1, $player->z),Block::get(42,0)); $player->addEffect(Effect::getEffect(9)->setDuration(100)->setAmplifier(9)); $level->addParticle(new PortalParticle(new Vector3($player->x, $player->y, $player->z))); } else { $sender->sendMessage("Player not found"); } } } }} the error :: "An unknown error occurred while attempting to perform this command" and thankis