I have this code: PHP: public function onCommand(CommandSender $sender, Command $command, $label, array $args): bool{ switch ($command->getName()) { case "coin": $coin = $this->getCoin($sender->getName()); $formattedcoin = $this->getFormattedCoin($coin); $form = new SimpleForm(function (Player $player, ?int $data) { if(!is_null($data)) { switch($data) { case 0: $this->viewCoins($player); break; case 1: $this->payCoins($player); break; case 2: $this->withdrawCoins($player); break; case 3: $this->topCoins($player); break; case 4: break; } } }); $form->setTitle("§c§l❖§eCoins Menu§c❖"); $form->setContent("§a§lCoins của bạn:§e $formattedcoin"); $form->addButton("§e§lXem coins của người khác"); $form->addButton("§e§lPay Coins"); $form->addButton("§c§l「Admin」§e Rút coins từ người khác!"); $form->addButton("§e§lTop Coins!"); $form->addButton("§cExit"); $sender->sendForm($form); return true; } } and PHP: public function viewCoins(Player $player){ $form = new CustomForm(function (Player $player, $data) { $ranhquama = $data[0]; $player2 = "$ranhquama"; if($data[0] == null || !$this->isRegistered($player2)){ $this->wrongInfomation($player); return true; } if(!$data[0] == null || $this->isRegistered($player2)){ $coins = $this->getCoin($player2); $player->sendMessage("§c§l❖§eCoins Menu§c❖§e>§r§a Coins của§e " . $player2->getName() . "§a là §e" . $coins); } }); $form->setTitle("§c§l❖§eCoins Menu§c❖"); $form->addLabel("§aĐiền tên người chơi bạn muốn xem"); $form->addInput("§eTên người chơi", "Steve"); } It work but when i clicked the first button, It didnt show anything.