custom fields input not displaying on preview or ads page

Hello,

custom fields are displayed on edit page but text that is input in field is not displayed properly on preview page. ive include the code i am using. would appreciate any help.

thank you

<?php
/**
* Plugin Name: [Adverts] Custom Fields API
* Version: 1.0
* Author: Greg Winiarski
* Description: This plugin explains how to create custom fields for Add Advert form.
*/
add_filter( “adverts_form_load”, “my_adverts_form_load” );
function my_adverts_form_load( $form ) {
if( $form[“name”] != “advert” ) {
return $form;
}

// add new custom field
$form[“field”][] = array(
“name” => “zip_code”,
“type” => “adverts_field_text”,
“order” => 25,
“label” => __( “zip code”, “adverts”),
“validator” => array(
array(
“name” => “string_length”,
“params” => array( “min” => 5 )

)
)
);

// add new custom field
$form[“field”][] = array(
“name” => “weight”,
“type” => “adverts_field_text”,
“order” => 25,
“label” => __( “weight”, “adverts”),
“validator” => array(
array(
“name” => “string_length”,
“params” => array( “min” => 3 )
)
)
);

return $form;

}

add_filter(“manage_edit-advert_columns”, “my_adverts_edit_columns”, 20);
function my_adverts_edit_columns( $columns ) {
$columns[“my_custom_column”] = “zip code”;
$columns[“my_custom_column”] = “weight”;
return $columns;
}
add_action(“manage_advert_posts_custom_column”, “my_adverts_manage_post_columns”, 10, 2);
function my_adverts_manage_post_columns( $column, $post_id ) {
if($column == “my_custom_column”) {
$cf = get_post_meta( $post_id, ‘zip code’, true );
$cf = get_post_meta( $post_id, ‘weight’, true );
if(empty($cf)) {
echo “Empty“;
} else {
echo ““.$cf.”“;
}
}
}

add_action( “adverts_tpl_single_details”, “my_adverts_tpl_single_details” );

function my_adverts_tpl_single_details( $post_id ) {

$cf = get_post_meta( $post_id, “zip_code”, true);

$cf = get_post_meta( $post_id, “weight”, true);

?>

<?php if(! empty($cf) ): ?>
<div class=”adverts-grid-row”>
<div class=”adverts-grid-col adverts-col-30″>
<span class=”adverts-round-icon adverts-icon-wordpress”></span>
<span class=”adverts-row-title”>zip code</span>
</div>
<div class=”adverts-grid-col adverts-col-65″>
<?php esc_html_e( $cf ) ?>
</div>
</div>
<?php endif; ?>

<?php if(! empty($cf) ): ?>
<div class=”adverts-grid-row”>
<div class=”adverts-grid-col adverts-col-30″>
<span class=”adverts-round-icon adverts-icon-wordpress”></span>
<span class=”adverts-row-title”>weight</span>
</div>
<div class=”adverts-grid-col adverts-col-65″>
<?php esc_html_e( join(“, “, $cf) ) ?>
</div>
</div>
<?php endif; ?>

<?php
}