Controller gives NullReferenceException and Teleporter is unresponsive when collided

I'm relatively new to the Unity Engine. I'm making a simple game where after the player collects every object in order to reach another scene. However, the teleporter has no response after the player collects every object and collides with the teleporter.

Does anyone know what might have gone wrong with my code? Any help would be appreciated. Thanks. Compiler Error Observation: Console gives a NullReference error everytime the game is running.

Controller.cs(C#)

 using UnityEngine;
 using UnityEngine.UI;
 using System.Collections;

 public class Controller : MonoBehaviour {
 public GameObject Ball;
 public float speed;
 public Text countText;
 public Text winText;
 
 private Rigidbody rb;
 private int count = 4;
 
 void Start ()
 {
     rb = GetComponent<Rigidbody>();
     count = 0;
     SetCountText ();
     countText.text = "";
     winText.text = "";
 }
 
 void FixedUpdate ()
 {
     float moveHorizontal = Input.GetAxis ("Horizontal");
     float moveVertical = Input.GetAxis ("Vertical");
     
     Vector3 movement = new Vector3 (moveHorizontal, 0.0f, moveVertical);
     
     rb.AddForce (movement * speed);
 }
 
 void OnTriggerEnter(Collider other)
 {
     if (other.gameObject.CompareTag ("Pickup"))
     {
         other.gameObject.SetActive (false);
         count = count + 1;
         SetCountText ();
         //Destroy (other.gameObject);
     }
 }
 
 void SetCountText ()
 {
     countText.text = "Count: " + count.ToString ();
     if (count == 4);
     {
         winText.text = "You Win!";
     }
 }

TeleportPad.cs

      public class TeleportPad : MonoBehaviour {
             
              private GameObject Teleport;
              public Text winText;      
             
              void Start ()
              {
                           winText.text = "";  
              }
       
             
              void OnTriggerEnter(Collider other)
              {
                  if (other.gameObject.CompareTag ("Teleport") &
                   winText.text == "You Win!")
                  {
                      gameObject.SetActive (true);
                      //Destroy (other.gameObject);
                      Application.LoadLevel(2);
                  }
       
              }      
          }  [2]: /storage/temp/54021-uniq.png