$result = $dbcon->query("SELECT * FROM PT_USERS WHERE Username = '$gebruiker' AND Password = '$wachtwoord'");
    while($row = $result->fetch_assoc()) {
        if($result->num_rows == 1) {
        $_SESSION['PT_USERS']       = $row["Username"];
        $_SESSION['PT_CONFIRM']     = $row["Confirmed"];
        header("Location: ../");
        }
        else {
            $result = $dbcon->query("SELECT * FROM PT_USERS WHERE Username = '$gebruiker'");
            if($result->num_rows == 1) {
                echo '<script>alert("Het wachtwoord klopt niet met dit gebruikersnaam!");</script>';
                header("Location: ../");
            }
            else {
                echo '<script>alert("Geen account gevonden!");</script>';
                header("Location: ../");
            }
        }
    }