TradeGUI plugin

uh hi can anyone help me with my code ?​

Im trying to make a tradeGUI
So if a player will enter the command /trade <playername> the other player should get a message like do /trade accept or decline

PHP:

<?php

namespace TradeGUI;

use pocketmine\Server;
use pocketmine\Player;
use pocketmine\plugin\PluginBase;

use pocketmine\utils\TextFormat as TF;

use pocketmine\event\Listener;

use pocketmine\command\Command;
use pocketmine\command\CommandSender;

class Trade extends PluginBase implements Listener{
    
    public function onEnable(){
        $this->getLogger()->info("[TradeGUI] Plugin Has Been Enabled");
    }
    
    public function onCommand(CommandSender $sender, Command $cmd, string $label, array $args) : bool {
        if($cmd->getName() == "trade"){
            if(!$sender instanceof Player){
                $sender->sendMessage("please use this command in-game");
                return false;
            }
            if(!isset($args[0])){
                $sender->sendMessage("§aUsage: §7/trade <name> \n §7<accept> \n §7<decline>")
            }else{
                
                $tradewith = $this->getServer()->getPlayer()->getName($args[0]);
                
                if($tradewith->isOnline()){
                    $sender->sendMessage("§cYou have sent a request to:" . $args[0]);
                    $tradewith->sendMessage($sender->getName() . "§cHas sent a request to trade do /trade <decline/accept>");
                }else{
                    $sender->sendMessage("§cPlayer is not online!");
                }
            }
            if($args[0] == "accept"){
                //do something
                }
            }
        }
        return true;
    }
}

 

I can't help you but I think you can use InvSee plugin to help you