//Additon by gal
global $post;
      $pid = $post->ID; //get current post id
              $phoneNumber = get_post_meta($pid, 'header_phone_number', true);
	$cat_id = get_query_var('cat');

     if ($phoneNumber=='') {
     	echo $cat_id;
     	$phoneNumber= get_option( "category_header_phone_".$cat_id);
     }