getConfig().set does not work correctly?

Question

I'm trying to make "/setspawn" command "/lv setspawn". I put the plugin inside "plugins" folder, the plugin generates the config and I'll open the config. Everything at this moment is right, so when I try to use "/lv setspawn" everything except cords get removed. I go to config and use "control+z" "control+s" and /reload. Now config is like at the first moment, I use again "/lv setspawn" and works perfectly (I can't put more than 2 links).

I'm sorry for my english.

What I want:

I want the coordinates are put inside the config when I use /lv setspawn

Video from the problem

Main code :

package com.gmail.santiagoelheroe;

import static com.gmail.santiagoelheroe.Eventos.plugin;
import org.bukkit.*;
import org.bukkit.command.Command;
import org.bukkit.command.CommandSender;
import org.bukkit.configuration.file.FileConfiguration;
import org.bukkit.entity.Player;
import org.bukkit.plugin.PluginManager;
import org.bukkit.plugin.java.JavaPlugin;

public class LoginVip extends JavaPlugin {

    // Comandos     
    @Override   
    public boolean onCommand(CommandSender sender, Command cmd, String label, String[] args) {

        if (args[0].equalsIgnoreCase("setspawn")) {
            getConfig().set("Cords.World", player.getLocation().getWorld().getName());
            getConfig().set("Cords.X", player.getLocation().getX());
            getConfig().set("Cords.Y", player.getLocation().getY());
            getConfig().set("Cords.Z", player.getLocation().getZ());
            saveConfig();     
            sender.sendMessage(prefix + "§aSpawn placed");
            return true;
        }

        if (args[0].equalsIgnoreCase("spawn")) {
            World w = Bukkit.getServer().getWorld(getConfig().getString("Cords.World"));  
            double x = getConfig().getDouble("Cords.X");
            double y = getConfig().getDouble("Cords.Y");
            double z = getConfig().getDouble("Cords.Z");
            player.teleport(new Location(w, x, y, z));
            return true;    
        }
        return true;        
   }


//Comandos   


   @Override
   public void onEnable() {  
       PluginManager manager = this.getServer().getPluginManager();
       manager.registerEvents(Eventos, this);
       saveDefaultConfig();   
   }

Config (inside the plugin)

# * Permisos: 'lv.main', 'lv.join' y 'lv.quit'  Variables: %player%
Configuracion:
  JoinMessage: '&b%player% &7se ha conectado'
  JoinMessageActivo: true
  QuitMessage: '&c%player% &7se ha desconectado'
  QuitMessageActivo: true
  NoPermissionsMessage: '&cNo tienes permisos para hacer esto'
  Prefix: '&7[&6LV&7] '
  TpSpawnOnJoin: false #To set spawn use in game /lv setspawn
Cords:
  World: ''
  X: ''
  Y: ''
  Z: ''

Answer 1

Personally, I hate the default config so I never use it. Take a look at YamlConfiguration. See a tutorial.

File fileConfig = new File(Plugin.getDataFolder().getPath(), "config.yml");
YamlConfiguration config = YamlConfiguration.loadConfiguration(fileConfig);

---

// Setting
Location spawn = Player.getLocation();
config.set("spawn.world", spawn.getWorld().getName());
config.set("spawn.x", spawn.getX());
config.set("spawn.y", spawn.getY());
config.set("spawn.z", spawn.getZ());
config.set("spawn.yaw", spawn.getYaw());
config.set("spawn.pitch", spawn.getPitch());
try {
    config.save(fileConfig);
} catch (IOException io) {
    // Unable to save data
}

// Getting
String world = config.getString("spawn.world");
double x = config.getDouble("spawn.x");
double y = config.getDouble("spawn.y");
double z = config.getDouble("spawn.z");
double yaw = config.getDouble("spawn.yaw");
double pitch = config.getDouble("spawn.pitch");
Location spawn = new Location(Server.getWorld(world), x, y, z, (float) yaw, (float) pitch);
Player.teleport(spawn);