跨多个页面存储会话表单数据[重复]

After hours of searching, i cant solve my Problem. All other Answers i found is just on the first page an form an not on other pages, dont work for me or explain it correctly. i think my code is correct but its shows like $email = $_SESSION['email']; is wrong or the code on the page before?

I want save the Input data from an form on Multiple Pages. i have 3 pages where the first two pages had an Form. The Problem i cant echo the email value from first page on the 3 Page.

Page 1:

<form class="" method="post" action="page2.php">
<input type="text" id="email" name="email" placeholder="email" />
<input type="submit" value="Next >"  />
</form>

Page 2:

<?php

session_start();

$_SESSION['email'] = $_POST['email'];

include("config.php");
?>
.............

<form class="" method="post" action="page2.php">
    <input type="text" id="password" name="password" placeholder="password" />
    <input type="submit" value="Next >"  />
    </form>

Page 3:

<?php

session_start();

$_SESSION['password'] = $_POST['password'];
$email = $_SESSION['email'];

include("config.php");
?>.

..............

<?php
echo $_POST["email"];
    ?>

Whats wrong with my Session code? Error on 3 Page is: Undefined index: email

</div>