FOUND IT !!!!!!!
In my template folder it has
/html/com_k2/itemform.php

and if you open it you are gonna see

<?php
/**
* @version $Id: itemform.php 1812 2013-01-14 18:45:06Z lefteris.kavadas $
* @package K2
* @author JoomlaWorks www.joomlaworks.net
* @copyright Copyright (c) 2006 - 2013 JoomlaWorks Ltd. All rights reserved.
* @license GNU/GPL license: www.gnu.org/copyleft/gpl.html
*/

// no direct access
defined('_JEXEC') or die;

?>


if you delete or rename the com_k2 folder in there it works perfectly I dont now why... but it works!!!

If you used the template override for your category listings, items, etc views you ned to keep the folder active and just remove this specific file from it so that the frontend editing file would show from the component's views and not the overrides.

You can also check for changes between the file itemform.php from your template folder and the one located in the components/com_k2/templates/ folder and make the appropriate changes to the one you have in your template folder. That way you can keep it.