how to do a if statement to activate and deactivate a button

So I wanted to add on to the roll-a-ball tutorial by adding some more complex levels to it. I am using buttons to go between the different scenes that have the different levels on them. What I have setup so far is to have my if statement refer to how many items have been collected (in this case two for the sake of time) to determine if I have won and to therefore pop up the button to change scenes. I am using "continueBtn.SetActive(true)/(false);" to deactivate and activate the button therefore "popping" it up. (refer to my script that I will be posting below if you are confused) My problem is that It won't be deactivated when I don't have those two items collected and it won't be active when I do have them. I have tried to replace the false with true and I have tried to delete the "else" portion of the statement and nothing truly works. I know my problem isn't that the script isn't attached to the button itself because I have checked that many times and with some of my experiments of deletion and replacement It sometimes is popped up before I even get those two items. (to understand what I have tried and and what I haven't look at my short vid (I will post a link below). THANKS FOR TAKING YOUR TIME TO HELP ME!! :)

Here is my short vid (I highly recommend you to watch it) : https://youtu.be/tryPRDXJH8k

You guys helped me last time I had a problem so I'm going to put your name here @NorthStar79 @EdwinChua (everybody ignored my last question once somebody typed one response but when I replied with their solution not working and put @their name they still didn't respond. So thats why im reposting this question).

Here is my script (the if then statement is at the bottom):

 public class PlayerController : MonoBehaviour {
 public float speed;
 public float time = 0;
 public Text countText;
 public Text winText;
 public int count;
 public GameObject ContinueBtn;
  

 private Rigidbody rb;
   

 void Start()
 {
     {
         rb = GetComponent<Rigidbody>();
         count = 0;
         SetCountText();
         winText.text = "";
         ContinueBtn.SetActive(false);
     }
 }


 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("Pick Up"))
     {
         other.gameObject.SetActive(false);
         count = count + 1;
         SetCountText();
     }
 }

 void SetCountText()
 {
     countText.text = "Count: " + count.ToString();
     if (count >= 18)
         winText.text = "You've won!";

     if (count >= 2)
     {
         ContinueBtn.SetActive(true);
     }
     else ContinueBtn.SetActive(false);
 }