NullReferenceException with GetComponent() C#

 public class PlayerSprite : MonoBehaviour 
 {
     protected ScrollControl scrollScript;
 
     void start()
     {
        scrollScript = gameObject.GetComponent<ScrollControl>();
     //scrollScript = gameObject.GetComponent("ScrollControl") as ScrollControl;
        scrollScripte.enabled = false;
     }
 }

I'm having NullReferenceException error during runtime for scrollScript.enabled = false; I've tried the both ways of initializing scrollScript but to no avail. Can someone help me T.T