Cakephp comment form input keeps the same value after i press add

I've created a blog site from "Beginning CakePHP from novice to professiona"-David Golding. I have the comment view listed below:

<?php echo $form->create('Comment');?>
<?php __('Add Comment');?> <?php echo $form->input('name'); echo $form->input('content'); echo $form->input('post_id'); ?>
<?php echo $form->end('Submit');?>
  • <?php echo $html->link(__('List Comments', true), array('action' => 'index'));?>
  • <?php echo $html->link(__('List Posts', true), array('controller' => 'posts', 'action' => 'index')); ?>
  • <?php echo $html->link(__('New Post', true), array('controller' => 'posts', 'action' => 'add')); ?>

The problem is after i press Submit the values remains in name and content fields.
Can anybody help me?