void SkorAyarla(int count) giving error

{
private Rigidbody2D myRigidbody;

private Animator myAnimator;
private int skor;
public Text toplamSkor;
[SerializeField]
private float hiz;
private bool sagaBak;

void Start()
{
    sagaBak = true;
    skor = 0;
    myRigidbody = GetComponent<Rigidbody2D>();
    myAnimator = GetComponent<Animator>();
}

void Update()
{
    float yatay = Input.GetAxis("Horizontal");
    TemelHareketler(yatay);
    Yoncevir(yatay);
}
private void TemelHareketler(float yatay)
{
    myRigidbody.velocity = new Vector2(yatay * hiz, myRigidbody.velocity.y);
    myAnimator.SetFloat("karakterHizi", Mathf.Abs(yatay));
}
private void Yoncevir(float yatay)
{
  
    if (yatay > 0 && !sagaBak || yatay < 0 && sagaBak)
    {

        sagaBak = !sagaBak;
        Vector3 yon = transform.localScale;
        yon.x *= -1;
        transform.localScale = yon;
    }

}
void OnCollisionEnter2D(Collision2D other)
{

    if (other.gameObject.tag == "altin")
        other.gameObject.SetActive(false);
        skor = skor + 100;
        SkorAyarla(skor);
}

}

void SkorAyarla(int count)

{

toplamSkor.text = count.ToString();

It looks like the SkorAyarla (int) function is outside your class and does not have a reference to the toplamSkor Text object.