OK, so have got
<?php if ($row_WADAlogins['UserPassword'] != $_POST['Confirm']) {
$_SESSION['PasswordChanged'] = true;
} ?>
and
<?php if($_SESSION["PasswordChanged"] = true ){ ?>
<span class="text-element requiredLabel" style="background: green; text-align:center;">Password successfully changed</span>
<?php } ?>
But the message is showing all the time....