I'm repeatedly getting a error which is something like - Assets/Scripts/GameManager.cs(7,22): error CS0101: The namespace `global::' already contains a definition for `GameManager'

Please help me!
my code is -
using UnityEngine;
using System.Collections;

using System.Collections.Generic;        

public class GameManager : MonoBehaviour
{
	public static GameManager instance = null;              
	private BoardManager boardScript;                    
    private int level = 3;                               
	
	void Awake()
	{
		if (instance == null)
			
		instance = this;
		else if (instance != this)
			
				Destroy(gameObject);
		DontDestroyOnLoad(gameObject);
		
		boardScript = GetComponent<BoardManager>();
		 
		InitGame();
	}
	
	void InitGame()
	{
		boardScript.SetupScene(level);
		
	}
	
	
	
	//Update is called every frame.
	void Update()
	{
		
	}
}

Game manger is already a named class file or namespace, just change your script’s name to something else or you can search your assets for “game manager” and delete the extra script. I also use a script called GameManager and have no problems (with unity 5.2.2) so you might have an extra file floating around