Space Shooter tutorial game won't restart

Questions & Answers
1

I get the error below and then I’m pointed to this code. The problem started after switched the GameController code to use the “UnityEngine.SceneManagement” function.

Now every time I press “R” to restart it turns off the Game Controller

Cannot find ‘GameController’ script
UnityEngine.Debug:Log(Object)
DestroyByContact:Start() (at Assets/Scripts/DestroyByContact.cs:24)

void Start ()
	{
		GameObject gameControllerObject = GameObject.FindGameObjectWithTag ("GameController");
		if (gameControllerObject != null)
		{
			gameController = gameControllerObject.GetComponent <Done_GameController>();
		}
		if (gameController == null)
		{
			Debug.Log ("Cannot find 'GameController' script");
		}
	}


using System.Collections;
using UnityEngine;
using UnityEngine.SceneManagement;

public class GameController : MonoBehaviour 
{
	public GameObject[] hazards;
	public Vector3 spawnValues;
	public int hazardCount;
	public float spawnWait;
	public float startWait;
	public float waveWait;

	public GUIText scoreText;
	public GUIText restartText;
	public GUIText gameOverText;

	private bool gameOver;
	private bool restart;
	private int score;

	void Start ()
	{
		gameOver = false;
		restart = false;
		restartText.text = "";
		gameOverText.text = "";
		score = 0;
		UpdateScore ();
		StartCoroutine (SpawnWaves ());
	}

	void Update ()
	{
		if (restart) 
		{
			if (Input.GetKeyDown (KeyCode.R))
			{
				SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex);
			}
		}
	}
2

@machado_ i have just done this tutorial and replace SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex);

with

Application.LoadLevel(Application.loadedLevel); as specified in the tutorial and it worked for me

and take off using UnityEngine.SceneManagement;

hope this works

,I’ve got this problem too