Why this Error when trying to add a score using the new GUI ?

OK so I'm trying to add a scoring system to my game and as such have been watching the new GUI tutorials. I thought I'd followed things to the letter but when I press play I get the following error -

NullReferenceException: Object reference not set to an instance of an object ScoreManager.Update () (at Assets/Scripts/ScoreManager.cs:25

my script is -

 using UnityEngine;
 using UnityEngine.UI;
 using System.Collections;
 
 public class ScoreManager : MonoBehaviour
 {
     public static int score;        // The player's score.
 
     Text text;                      // Reference to the Text component.
     
     
     void Awake ()
     {
         // Set up the reference.
         text = GetComponent <Text> ();
         
         // Reset the score.
         score = 0;
     }
     
     
     void Update ()
     {
         // Set the displayed text to be the word "Score" followed by the score value.
         text.text = "S c o r e : " + score;
     }
 }
 

I have my canvas, with a text component. The text component (ScoreText) has the above script attached to it as described in the tutorial.

Either I've missed something which I just can't see (even after multiple times watching) or I simply don't understand what the guys are trying to tell me.

Any suggestions plz ???