Not sure why I'm getting a null reference exception

I have a script that uses raycasting to detect if the character is looking at a footlocker, and if they are and the E key is pressed down it open or closes that individual footlocker, and not the others in the scene. However I keep getting a null reference exception and I'm not sure why.

Any help would be greatly appreciated.

The raycasting script

 using UnityEngine;
 using System.Collections;
 
 public class ActionButtonScript : MonoBehaviour 
 {
     int i = 0;
     public float playerReach = 4.0f;
 
     void Update () 
     {
         CrossHairScript crossHairScript = GetComponent<CrossHairScript>();
         RaycastHit target = new RaycastHit();
         Vector3 fwd = transform.TransformDirection(Vector3.forward); 
     
         Debug.DrawRay(transform.position, fwd,Color.red);
         if (Physics.Raycast(transform.position, fwd, out target, playerReach))
         {    
             if(target.collider.gameObject.tag == "Openable Door")
             {
                 crossHairScript.x = 1; //Changes color of crosshair;
                 GameObject currentDoor = target.collider.gameObject;
                 DoorOpenerScript doorOpenerScript = currentDoor.GetComponent<DoorOpenerScript>();
                 if(Input.GetKeyDown(KeyCode.E)) 
                 {
                     doorOpenerScript.toggleOpen(); // where the error occurs
                 }
             }
             else
             {
                 crossHairScript.x = 0; //Reverts crosshair to default;
             }
         }
         
     }
 }

The doorOpenerScript

 using UnityEngine;
 using System.Collections;
 
 public class DoorOpenerScript : MonoBehaviour 
 {
 
     float smooth = 2.0f;
     public float openAngle = 90.0f;
     public float closeAngle = 0.0f;
     public bool open = false;
 
     public void OpenAndClose(bool opened)
     {
         if (opened)
         {
             Quaternion target = Quaternion.Euler(new Vector3(openAngle,270,180));
             transform.localRotation = Quaternion.Slerp(transform.localRotation,target, Time.deltaTime * smooth);
         }
         else
         {
             Quaternion target2 = Quaternion.Euler(new Vector3(closeAngle,270,180));
             transform.localRotation = Quaternion.Slerp(transform.localRotation,target2, Time.deltaTime * smooth);
         }
     }
     // Update is called once per frame
     void Update () 
     {
         if (Input.GetKeyDown(KeyCode.Y))
             toggleOpen();
         
         OpenAndClose(open);
     }
     public void toggleOpen()
     {
         open = !open;
     }
 
 }

EDIT: I found out the problem, DoorOpenerScript was actually attached to a child of the "Openable door"