Destroy() of an instance

/**
     * Destroys the instance, and removes it from the config "instances.yml"
     */
    public void destroy(){
        instanceFinishEvent event = new instanceFinishEvent(getHomeLocation().getWorld().getChunkAt(chunkX, chunkZ));
        Bukkit.getServer().getPluginManager().callEvent(event);

        IDinstance.remove(getID());
        instanceLocation.remove(world + chunkX + chunkZ);

        YamlConfiguration instances = YamlConfiguration.loadConfiguration(new File(InstancesBase.plugin.getDataFolder(),"instances.yml"));
        List<String> list = instances.getStringList(type.toString());
        if (list != null){
            if (list.contains(world + ":" + chunkX + ":" + chunkZ)){
                list.remove(world + ":" + chunkX + ":" + chunkZ);

                instances.set(type.toString(), list);

                 try {
                     instances.save(new File(InstancesBase.plugin.getDataFolder(),"instances.yml"));
                 } catch (IOException e) {
                     System.out.print("Unable to save the 'instances.yml'. Is the disk full?");
                 }
            }
        }
    }