Kontoru-sama Desu!

<?php
include 'koneksi.php';
if (isset($_POST['btnReset']))
{
    $username = $_POST['username'];
    $cek = mysqli_query($koneksi,"select tiket from penumpang where username= '$username'");
    if(mysqli_num_rows($cek) == 1 )
    {
        $password = $_POST['password'];
        $repassword = $_POST['repassword'];
        if($password != $repassword)
        {
            ?>
                <script>
                    alert("inputan password tidak sama");
                    window.location.href = 'lupa.php';
                </script>
            <?php
        } else {
            $password = md5($password);
            $sql = mysqli_query($koneksi,"UPDATE penumpang SET password = '$password' WHERE username = '$username'");
            if($sql)
            {
                ?>
                    <script>
                        alert("Password telah di Perbarui");
                        window.location.href = 'login.php';
                    </script>
                <?php
            } else {
                ?>
                    <script>
                        alert("Password gagal di Perbarui");
                        window.location.href = 'lupa.php';
                    </script>
                <?php
            }
        }
    } else {
        ?>
            <script>
                alert("Pastikan username yang anda masukan Benar");
                window.location.href = 'lupa.php';
            </script>
        <?php
    }
}
?>