Unity 3D Error CS0103 "The name 'roomNameInputField' does not exist in the current context" hatası

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

public class Launcher : MonoBehaviourPunCallbacks
{
    // Start is called before the first frame update
    void Start()
    {
        Debug.Log("Bağlanıyor...");
        PhotonNetwork.ConnectUsingSettings();
    }

    public override void OnConnectedToMaster()
    {
        Debug.Log("Bağlandı.");
        PhotonNetwork.JoinLobby();
    }

    public override void OnJoinedLobby()
    {
        MenuManager.Instance.OpenMenu("title");
        Debug.Log("Lobiye Bağlandı");
    }

    public void CreateRoom()
    {
        if(string.IsNullOrEmpty(roomNameInputField.text))
        {
            return;
        }
        PhotonNetwork.CreateRoom(roomNameInputField.text);
        MenuManager.Instance.OpenMenu("loading");

    }

    public override void OnJoinedRoom()
    {

    }

    public override void OnCreateRoomFailed(short returnCode, string message)
    {
        MenuManager.Instance.OpenMenu("room");
    }
}

public InputField roomNameInputField;