title: add telephone number at checkout in opencart
body: <p>im trying to add a filed to the checkout page to request a telephone number beofre the order is processed.</p>
  
  <p>Im my checkout.tpl i have added</p>
  
  <pre><code> &lt;label for"telephone"&gt;Phone Number&lt;/label&gt;&lt;input type="text" name="telephone" value="&lt;?php echo $telephone; ?&gt;" required="required" /&gt;
  </code></pre>
  
  <p>in the checkout.php controller</p>
  
  <pre><code>$this-&gt;data['telephone'] = $this-&gt;customer-&gt;getTelephone();
  </code></pre>
  
  <p>So it displays the available telephone number in the profile by default and gives the chance for the user to change it.</p>
  
  <p>But the problem im having is when i a order is processed with a new phone number, in the order it saves the old number. </p>
  
  <p>when i print the value in <code>$this-&gt;request-&gt;post['telephone']</code> it says</p>
  
  <blockquote>
    <p>Undefined index: telephone</p>
  </blockquote>
  
  <p>even that input filed holds a value. Can someone please tell me what am i doing wrong here?</p>