Solved [Problem] NullPointerException without sense.

I have a problem at my plugin, config and the inventories.

Explanation:
These are my inventories.

Code (Text):

    Inventory staffInv = Bukkit.createInventory(null, 54, this.getConfig().getString("GUI.MenuName"));
    Inventory optionsMenu = Bukkit.createInventory(null, 54, this.getConfig().getString("GUI.OptionsAndStatsMenuName"));

When I load them, I receive an error in the console.
Yep, the NullPointerException referring to the "this.getConfig()".

All config is perfect, and if you want, here's the full code:
(The inventories are at the line 735 & 736)

https://github.com/MrLechuga/SimpleStaffControl2/blob/master/MClass.java



I'll give you a potato if you help me!

 

It's not. I tested using strings without getting it from config, and it works at this way, but I want that the user can config the menu name.
Example:

Code (Text):

Inventory staffInv = Bukkit.createInventory(null, 54, "Staff List!";

 

Reload the page, I edited that reply.
And the path/config isn't null. I used /test commands that gives me all paths, and all works fine

 

Hours searching, and no one knows why the problem is happening...

P.S. Sorry if my english sucks.

 

The problem is the following:
I re-written my code 3 times for the same error.
I used different ways to fix it, like making methods for the strings

I don't know what to do

 

Like in the title...
It has no sense.

 

There's a way to change an inventory's name?
If it's, I can test editing it when a player opens it.