Unable to load next level, skips to level 3 instead of going to level 2 or else does not load next level at all

I am completely new to this C# stuff but I am getting the hang of it. I have been making a game and what happened at first is It would not load level 1 to level 2 it would give me a error like could not load level 2 as it is not in buld setting etc. Before you say is it in building sets the answer is yes it is. So I made a 3rd level well, now it’s going from level 1 to level 3 no2 instead and is still refusing to load level 2. Here is my line of code

using UnityEngine;
using System.Collections;

public class GameManager : MonoBehaviour {
	public static int currentScore;
	public static int highscore;

	public static int currentLevel = 0;
	public static int unlockedLevel;

	public static void CompleteLevel()
		currentLevel += 1;
		Application.LoadLevel(currentLevel + 1);


Here are some screen shots as well.
(Just hit next image to see my levels are created)

hi,Why are you incrementing the currentLevel count twice ?The code is doing what you have written.If you have all three scenes in the build settings,just increment and call the next scene

public class GameManager:MonoBehaviour

  public static in currentLevel=0;
  int MaxLevelCount=3;

  public static void OnCompleteLevel()
        //Increment current level count
        //Load the new Level

         //Maximum scenes reached
         Debug.Log("No more levels to Load");

         //Or you can reset the level count to zero and load the     first level again