How to run a script twice in a scene

Hey,

I've got a scene and it's basically a store, and I got a script (in C#) that disables a canvas until the loading screen has finished, when I run it for the first time it works perfectly, but when I click a back button that I implemented in the game and go back to the store scene the script that disables the canvas does not run.

My only guesses are is that unity does not run a script when it's already been run, is there a way around that?

Thanks, Nathan.

Here's my script that does the job for me in case you need it:

 using UnityEngine;
 using UnityEngine.UI;
 using System.Collections;
 using System.Diagnostics;
 public class ProgressBar : MonoBehaviour
 {
     public Image circularSilder;            
     public float time;
     public Canvas loadingBar;
     public Canvas playMenu;
     public Canvas money;
     private float loadingTime;
     public float fadeTime;
 
     public void Start()
     {
         loadingTime = Random.Range(1f, 4f);
 
         StartCoroutine(Example());
 
         circularSilder.fillAmount = 0f;
     }
     public IEnumerator Example()
     {
         print(Time.time);
         yield return new WaitForSeconds(4);
         //fade it out
         CanvasGroup canvasGroup = GetComponent<CanvasGroup>();
         while (canvasGroup.alpha > 0)
         {
             canvasGroup.alpha -= Time.deltaTime / fadeTime;
             yield return null;
         }
         DestroyObject(loadingBar);
         print("Loaded Store");
         loadingBar.enabled = false;
         playMenu.enabled = false;
         money.enabled = true;
         Time.timeScale = 1;
 
     }
 
     public void Update()
     {
         circularSilder.fillAmount += Time.deltaTime / loadingTime;
 
     }
 }