Incorrect reading of an array

I am working in c-sharp .net and I am working on creating a login screen for my project. I have a text file with login info for all the users. My c-sharp scrip reads that file to a string then cuts it up into two lists, _usernames and _passwords. When the user types their login info and hits login the _usernames[0] and _passwords[0] account info are the only ones that work. What I want it to do is look through all the _usernames for the inputted one, if it finds it then check the _password[same index as _usernames] and if both are the same as what the user submitted then it will add "true" to the richTextBox.

Why is it not correctly reading from the array?

This is my users.txt:

admin,test|
andrew,yeet|
zana,happy|

This is my c-sharp script:

using System;
using System.IO;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace BaseUserInterfase
{
    public partial class Login : Form
    {
        string path = Directory.GetCurrentDirectory() + "\\data\\users.txt";
        string data;
        string[] _usernames = new string[10];
        string[] _passwords = new string[10];

        public Login()
        {
            InitializeComponent();
        }

        private void Login_Load(object sender, EventArgs e)
        {
            GetLoginData();
        }

        private void btnLogin_Click(object sender, EventArgs e)
        {
            rtbTemp.Text = "";
            for(int i = 0; i < _usernames.Length; i++)
            {
                if(_usernames[i] == null)
                {
                    break;
                }

                rtbTemp.AppendText("\n" + _usernames[i]);
                rtbTemp.AppendText("\n" + tbUsername.Text.ToString());

                rtbTemp.AppendText("\n" + _passwords[i]);
                rtbTemp.AppendText("\n" + tbPassword.Text.ToString());

                if (_usernames[i] == tbUsername.Text.ToString())
                {
                    rtbTemp.AppendText("\nUsername true");
                    if (_passwords[i] == tbPassword.Text.ToString())
                    {
                        rtbTemp.AppendText("\nPassword true");
                        rtbTemp.AppendText("\ntrue");
                        return;
                    }
                }
            }
            rtbTemp.AppendText("\nfalse");
        }

        public void GetLoginData()
        {
            using (StreamReader streamReader = new StreamReader(path, Encoding.UTF8))
            {
                data = streamReader.ReadToEnd();
            }

            List<string> _data = data.Split('|').ToList();
            _data.RemoveAt(_data.Count - 1);

            rtbTemp.AppendText("\n");

            Array.Resize<string>(ref _usernames, _data.Count);
            Array.Resize<string>(ref _passwords, _data.Count);

            foreach (string _item in _data)
            {
                List<string> userdata = _item.Split(',').ToList();

                string username = userdata[0].ToString();
                string password = userdata[1].ToString();

                Console.WriteLine(_item);
                Console.WriteLine(username);
                Console.WriteLine(password);


                for(int i = 0; i < _data.Count; i++)
                {
                    if(_usernames[i] == null)
                    {
                        _usernames[i] = username;
                        _passwords[i] = password;
                        break;
                    }
                }
            }
        }

        private void btnExit_Click(object sender, EventArgs e)
        {
            Application.Exit();
        }
    }
}

And this is an image of the login screen:
1

>Solution :

Your file contains carriage return characters. Remove them before you split its content

data = streamReader.ReadToEnd().Replace("\r\n", "");