Trying to get bookmeta data to save

so i have this:
EventHandler
public void OnPlayerFirstJoin(PlayerJoinEvent event){
Boolean first = event.getPlayer().hasPlayedBefore();

if (first == true){
return;
}
Player player= event.getPlayer();
Inventory inv= player.getInventory();

ItemStack book= new ItemStack(Material.WRITTEN_BOOK);
BookMeta sbook= (BookMeta)book.getItemMeta();
sbook.setTitle(config_.getTitle());
sbook.setAuthor(config_.getAuthor());
sbook.setPages(config_.getPages());

book.setItemMeta(sbook);

inv.addItem(book);



}

When i first log in the book is there but the author isnt, or text, or the title.

 

There may be an error in one of your methods from the "config_" variable.

 

How did you define config_?