Solved Stop/Reload new yml file problem.

hey guys i tried a few stuff before posting this so i'm really tired i'm trying for hours to create new file and stuff.
so my problem is that when i do for example /reloadgui this will reload in game the changes and save them (no problem with that) after that when i close the server and i open the market.yml file the changes i made are still there but when i open the server the changes goes to the default ones i have set before. Same is happening when reloading the server. Anyone help?
this is how market.yml looks

Code (Text):

ArmorShop[GUI]:
  Slot[1]:
    Lore: '&7Cost is: &e25.000 &9Points'
 

and this is the whole code in the main class.
[

Code (Text):

    public File MarketFile= new File(getDataFolder(), "market.yml");
    public FileConfiguration MarketConfig= YamlConfiguration.loadConfiguration(MarketFile);

    public void onEnable() {
        getConfig().options().copyDefaults(true);
        saveConfig();
        onGUI(); //the market stuff
        Bukkit.getServer().getPluginManager().registerEvents(this, this);
        Bukkit.getConsoleSender().sendMessage(ChatColor.RED + "----------------------------------------------------");
        if (!setupEconomy() ) {
            log.severe(String.format("[%s] - Disabled due to no Vault dependency found!", getDescription().getName()));
            getServer().getPluginManager().disablePlugin(this);
            return;
        }
   
        if(!MarketFile.exists()){
            try {
                MarketFile.createNewFile();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
   
            try {
                MarketConfig.save(MarketFile);
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
    }

    private void reloadMarket(){ //this is for the reloading and saving command
        try {
            MarketConfig.load(MarketFile);
            MarketConfig.save(MarketFile);
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (InvalidConfigurationException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

     // this might be the problem that cause this because it has a default set and when i turn off my server or reload it might adding back the default  "&7Cost is: &e25.000 &9Points");
       private void onGUI(){
        MarketConfig.set("ArmorShop[GUI].Slot[1].Lore", "&7Cost is: &e25.000 &9Points");
        try {
            MarketConfig.save(MarketFile);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

   //economy
    private boolean setupEconomy() {
        if (getServer().getPluginManager().getPlugin("Vault") == null) {
            return false;
        }
        RegisteredServiceProvider<Economy> rsp = getServer().getServicesManager().getRegistration(Economy.class);
        if (rsp == null) {
            return false;
        }
        econ = rsp.getProvider();
        return econ != null;
    }
    //disable nothing added here about market.yml
    public void onDisable() {
        saveConfig();
        Bukkit.getConsoleSender().sendMessage(org.bukkit.ChatColor.GREEN + "------------------------------ " + getDescription().getVersion());
    }

 

i think so hmm but where i have to add this?

 

// SOLVED - LOCKED i had to move this MarketConfig.set("ArmorShop[GUI].Slot[1].Lore", "&7Cost is: &e25.000 &9Points"); here

Code (Text):

if(!MarketFile.exists()){
            try {
                MarketFile.createNewFile();
                MarketConfig.set("ArmorShop[GUI].Slot[1].Lore", "&7Cost is: &e25.000 &9Points");

than creating new called GUI and save it.
also i had to add in onEnable this MarketConfig.options().copyDefaults(true); thanks to @SoftSilk