Why cant i see my custom field ?.

My Custom Post Taxonomy Code

<?php
/* Special Offer Post */

add_action('init', 'special_offers');
function special_offers()
{
  $labels = array(
    'name' => _x('special offers', 'post type general name'),
    'singular_name' => _x('special_offer', 'post type singular name'),
    'add_new' => _x('Add New', 'special offers'),
    'add_new_item' => __('Add New special offers'),
    'edit_item' => __('Edit special offers'),
    'new_item' => __('New special offers'),
    'view_item' => __('View special offers'),
    'search_items' => __('Search special offers'),
    'not_found' =>  __('No special_offerss found'),
    'not_found_in_trash' => __('No special offerss found in Trash'),
    'parent_item_colon' => ''
  );
  $args = array(
    'labels' => $labels,
    'public' => true,
    'publicly_queryable' => true,
    'show_ui' => true,
    'query_var' => true,
    'rewrite' => true,
    'capability_type' => 'post',
    'hierarchical' => true,
    'menu_position' => 6,
	'_builtin' => false,
	'menu_icon' => get_bloginfo('template_directory') . '/images/special-offer-icon.png',  // Icon Path
    'supports' => array('title','editor','thumbnail','cats' , 'brands')
  );
  register_post_type('special_offers',$args);
}

register_taxonomy( 'brands', 'special_offers', array( 'hierarchical' => true, 'label' => __('Brands'), 'query_var' => 'brands' ) );

add_action( 'admin_init', 'my_admin3' );

function my_admin3() {
    add_meta_box( 'special_offer_meta_box',
        'special offer Details',
        'display_special_offer_meta_box',
        'special_offer', 'normal', 'high'
    );
}

?>

<?php
function display_special_offer_meta_box( $special_offer ) {

    $post_description = esc_html( get_post_meta( $special_offer->ID, 'post_description', true ) );
	$post_description2 = esc_html( get_post_meta( $special_offer->ID, 'post_description2', true ) );
    ?>
    <table>
        <tr>
            <td style="width: 100%">Post Description[For Home Page]</td>
            <td><input type="text" size="80" name="special_offer_post_description" value="<?php echo $post_description; ?>" /></td>
        </tr>
		<tr>
            <td style="width: 100%">Post Description 2[For Home Page]</td>
            <td><input type="text" size="80" name="special_offer_post_description2" value="<?php echo $post_description2; ?>" /></td>
        </tr>
    </table>
    <?php
}
?>
<?php
add_action( 'save_post', 'add_special_offer_fields', 10, 2 );

function add_special_offer_fields( $special_offer_id, $special_offer ) {

    if ( $special_offer->post_type == 'special_offers' ) {

        if ( isset( $_POST['special_offer_post_description'] ) && $_POST['special_offer_post_description'] != '' ) {
            update_post_meta( $special_offer_id, 'post_description', $_POST['special_offer_post_description'] );
        }
         if ( isset( $_POST['special_offer_post_description2'] ) && $_POST['special_offer_post_description2'] != '' ) {
            update_post_meta( $special_offer_id, 'post_description2', $_POST['special_offer_post_description2'] );
        }
    }
}

Custom fields not showing in my editor

<div class="offer-post">

<?php
$myquery['tax_query'] = array(
'relation' => 'OR',
array(
'taxonomy' => 'brands',
'terms' => array('ALL'),
'field' => 'slug',
),
array(
'taxonomy' => 'media',
'terms' => array('news', 'events'),
'field' => 'slug',
),
);
query_posts($myquery);

?>

<?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>
<div class="so-post-hom">
<h2 class="post-title"><?php the_title();?></h2><br />
<h3 class="post-desc"></h3>
<div class="post-bar">
<a href="">Go!</a>
</div>
</div>

<?php endwhile; else: ?>
<?php endif; ?>

and this code working, but in another custom post

<?php  echo esc_html( get_post_meta( get_the_ID(), 'employed_since', true ) ); ?>

please help me to correct the code.
i need to show the custom field(post_description)inside <h3 class=”post-desc”></h3>
and why can’t i see the custom field in editor ?
also if one field, what changes in the code ?