How to start dialog on differently and continue as long as player presses "E" key?

Hello. I have made a universal Dialog Manager that has DialogManager script. In one scene I have "Terminal" GameObject that starts dialog when player is in range and presses "E" and in the Battle scene dialog starts automatically when the player wins or loses a battle (condition in BattleManager script).

Terminal.cs:

 public class Terminal : MonoBehaviour
 {
     private Animator anim;
 
     private GameObject clue;
 
     [SerializeField]
     private DialogManager manager;
     [SerializeField] 
     private string[] lines;
     private bool inRange;
 
     // Use t$$anonymous$$s for initialization
     void Start()
     {
         anim = GetComponent<Animator>();
 
         clue = GameObject.FindGameObjectWithTag("Player").transform.GetC$$anonymous$$ld(0).gameObject;
     }
 
     // Update is called once per frame
     void Update()
     {    
         if (inRange && Input.GetKeyDown(KeyCode.E))
             manager.Write(lines);
     }
 
     private void OnTriggerEnter2D(Collider2D collision)
     {
         if (collision.gameObject.CompareTag("Player"))
         {
             inRange = true;
 
             anim.SetBool("inRange", true);
             clue.SetActive(true);
             clue.GetComponent<Animator>().SetInteger("clue", 1);
         }
     }
 
     private void OnTriggerExit2D(Collider2D collision)
     {
         if (collision.gameObject.CompareTag("Player"))
         {
             inRange = false;
 
             anim.SetBool("inRange", false);
             clue.SetActive(false);
             clue.GetComponent<Animator>().SetInteger("clue", 0);
             manager.textBox.SetActive(false);
         }
     }
 }

BattleManager.cs:

 public class BattleManager : MonoBehaviour
 {
     private string[] defeat = { "You are defeated!" };
     private string[] victory = { "Enemy has been defeated!", "You are victorius!" };
 
     private GameObject player;
     private GameObject enemy;
 
     [SerializeField]
     private DialogManager dManager;
     [SerializeField]
     private SceneManager2 sManager;
 
     void Start()
     {
         player = GameObject.FindGameObjectWithTag("Player");
         enemy = GameObject.FindGameObjectWithTag("Enemy");
     }
 
     void Update()
     {
         if (player == null) {
             Debug.Log("You have lost!");
             dManager.Write(defeat);
         }
 
         if (enemy == null) {
             Debug.Log("You have won!");
             dManager.Write(victory);
         }
     }
 }

Here is my attempt, but I get index out of bounds for some reason.

DialogManager.cs:

 public class DialogManager : MonoBehaviour
 {
     public GameObject textBox;
     private TMP_Text dialogText;
     
     private bool running;
 
     [SerializeField]
     private int index = -1;
 
     void Start()
     {
         textBox = transform.GetC$$anonymous$$ld(0).gameObject;
         dialogText = textBox.GetComponentInC$$anonymous$$ldren<TextMeshProUGUI>();
     }
 
     public void Write(string[] lines)
     {
         textBox.SetActive(true);
         StartCoroutine(Write(lines[++index]));
 
         if (Input.GetKeyDown(KeyCode.E) && !running)
         {
             if (textBox.activeInHierarchy && index > lines.Length - 2)
             {
                 textBox.SetActive(false);
                 index = -1;
             }
             else
             {
                 if (index < lines.Length)
                     StartCoroutine(Write(lines[++index]));
             }
         }
     }
 
     private IEnumerator Write(string line)
     {
         running = true;
         dialogText.text = "";
 
         foreach (char c in line)
         {
             dialogText.text += c;
             yield return new WaitForSeconds(0.01f);
         }
 
         running = false;
     }
 }