Bug Fixed issue don't post pls

Hey everyone, I was watching this video for a dialogue system. I followed every step my code was right but I get an error unlike others.

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

public class Dialogue : MonoBehaviour
{
public TextMeshProUGUI textComponent;
public string[] lines;
public float textSpeed;

private int index=0;

// Start is called before the first frame update
void Start()
{
textComponent.text = string.Empty;
StartDialogue();
}

// Update is called once per frame
void Update()
{
if (Input.GetKey(KeyCode.Space))
{
if (textComponent.text == lines[index])
{
NextLine();
}
else
{
StopAllCoroutines();
textComponent.text = lines[index];
}
}
}

void StartDialogue()
{
index = 0;
StartCoroutine(TypeLine());
}

IEnumerator TypeLine()
{
foreach (char c in lines[index].ToCharArray())
{
textComponent.text += c;
yield return new WaitForSeconds(textSpeed);
}
}

void NextLine()
{
if (index < lines.Length - 1)
{
index++;
textComponent.text = string.Empty;
StartCoroutine(TypeLine());
}
else
{
gameObject.SetActive(false);
}
}

}
This is the code, and these are the error im receiving from Unity.

IndexOutOfRangeException: Index was outside the bounds of the array.
Dialogue+<TypeLine>d__7.MoveNext () (at Assets/Scripts/Dialogue.cs:46)
UnityEngine.SetupCoroutine.InvokeMoveNext (System.Collections.IEnumerator enumerator, System.IntPtr returnValueAddress) (at <c399efc08928422d8828d74a2b19ffba>:0)
UnityEngine.MonoBehaviour:StartCoroutine(IEnumerator)
Dialogue:StartDialogue() (at Assets/Scripts/Dialogue.cs:41)
Dialogue:Start() (at Assets/Scripts/Dialogue.cs:18)



IndexOutOfRangeException: Index was outside the bounds of the array.
Dialogue.Update () (at Assets/Scripts/Dialogue.cs:26)

I'd like to hear some solutions from you.