question

I am developing a project using playfab + photon cs. I am creating a user with playfab with I set up photon rooms with cs in the second scene, but how can I use the playfab username in photon

 public void OnLoginButtonClicked()
    {
        string playerName = playerNameInput.text;
        if (!string.IsNullOrEmpty(playerName))
        {
            PhotonNetwork.LocalPlayer.NickName = playerName;
            PhotonNetwork.ConnectUsingSettings();
        }
        else
        {
            Debug.Log("Playername is invalid!");
        }
    }

How can I use the playfab username in the line LocalPlayer.NickName in this line ??