Formularz logowania problem z uzytkownikiem

Siemka mam taki problem, przy próbie uruchomienia programu i wpisaniu danych logowania wyskakuje mi "złe dane" chociaż wszystko jest dobrze. Dopiero za którymś razem uda sie zalogować.
Oto kod:

using System;
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 Formularz_do_logowania_LP
{
    public partial class STRONA_LOGOWANIE : Form
    {
        public STRONA_LOGOWANIE()
        {
            InitializeComponent();
            CreateUsers();
        }

        private void STRONA_LOGOWANIE_Load(object sender, EventArgs e)
        {

        }

        private void LOGIN_TEXT_BOX_TextChanged(object sender, EventArgs e)
        {

        }

        private void PASSWORD_TEXT_BOX_MaskInputRejected(object sender, MaskInputRejectedEventArgs e)
        {

        }

        private void LOGIN_BUTTON_Click(object sender, EventArgs e)
        {
            string uzytkownik = this.LOGIN_TEXT_BOX.Text;
            string haslo = this.PASSWORD_TEXT_BOX.Text;
            for (int i = 0; i < tableuser.GetLength(0); i++)

            {
                if (tableuser[i, 0] == uzytkownik && tableuser[i, 1] == haslo && tableuser[i, 2] == "ADMIN_FORM")
                {
                    MessageBox.Show("Jest w systemie", "Zalogowano");
                    
                    ADMIN_FORM fr = new ADMIN_FORM();
                    fr.Show();
                    break;
                }
                else if (tableuser[i, 0] == uzytkownik && tableuser[i, 1] == haslo && tableuser[i, 2] == "USER_FORM")
                {
                    MessageBox.Show("Jest w systemie", "Zalogowano");

                    USER_FORM fr = new USER_FORM();
                    fr.Show();
                    break;
                }

                else
                    MessageBox.Show("Zly login lub haslo", "Nie zalogowano");
                //return;
            }

        }
        
        string[,] tableuser = new string[6, 3];
        private void CreateUsers()
        {
            tableuser[0, 0] = "admin";
            tableuser[0, 1] = "admin";
            tableuser[0, 2] = "ADMIN_FORM";

            tableuser[1, 0] = "admin2";
            tableuser[1, 1] = "admin2";
            tableuser[1, 2] = "ADMIN_FORM";

            tableuser[2, 0] = "user1";
            tableuser[2, 1] = "123";
            tableuser[2, 2] = "USER_FORM";

            tableuser[3, 0] = "user2";
            tableuser[3, 1] = "123";
            tableuser[3, 2] = "USER_FORM";

            tableuser[4, 0] = "user3";
            tableuser[4, 1] = "123";
            tableuser[4, 2] = "USER_FORM";

            tableuser[5, 0] = "user4";
            tableuser[5, 1] = "123";
            tableuser[5, 2] = "USER_FORM";
        }

        private void label2_Click(object sender, EventArgs e)
        {

        }

        private void label1_Click(object sender, EventArgs e)
        {

        }

        private void button1_Click(object sender, EventArgs e)
        {
            Application.Exit();
        }
    }
}

Proszę o pomoc.