Object reference not set to an instance of an object. What could be the problem?

Question

Unity

I am trying to repeat the code from this video

CardInfoScr.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using TMPro;



public class CardInfoScript : MonoBehaviour
{
  public Card SelfCard;
  public Image Logo;
  public TextMeshProUGUI Name;
  
  public void ShowCardInfo(Card card)
  {
    SelfCard = card;
    
    
    
    // Ошибка
    Name.text = card.Name;
    
    
    Logo.sprite = card.Logo;
    Logo.preserveAspect = true;
    
    
    
  }
  
  private void Start(){
    ShowCardInfo(CardManager.AllCards[transform.GetSiblingIndex()]);
  }
  
  
}

But I am getting an error

NullReferenceException: Object reference not set to an instance of an object
CardInfoScript.ShowCardInfo (Card card) (at Assets/Scripts/CardInfoScript.cs:22)
CardInfoScript.Start () (at Assets/Scripts/CardInfoScript.cs:33)

Can anyone explain what is the reason?
I understand that the Card Pixel should have the names Name and Logo
But I have them.

Answer 1

Must be Name and Logo

Not the names of objects in the scene should be, but the variables in the script should contain references to objects.