Edit xml file - problem

[kkkk]

Uncaught exception 'DOMException' with message 'Not Found Error' on line:

$xml_Document->replaceChild($newTemplate_name,$oldTemplate_name);

xml file - xml_mail_format2.xml

<?xml version="1.0" encoding="ISO-8859-1"?>
<Email>
<Template>
Temaplate1
</Template>
<Temp>
Template2
</Temp>
</Email>

php file - xml_experiments.php

<?php
include('header.php');

$xml_Document= new DOMDocument("");

$xml_Document->formatOutput = true;

$xml_Document->preserveWhiteSpace = false;

$xml_Document->load('xml_mail_format2.xml');

$oldTemplate_name = $xml_Document->getElementsByTagName('Template')->item(0);

$newTemplate_name = $xml_Document->createElement('Template','asdfsdsdf');

echo $newTemplate_name->nodeValue;

$xml_Document->replaceChild($newTemplate_name,$oldTemplate_name);