how to add the shortcode in my file?

Hello, congratulations on the product, I like it.
I’m still testing, but I have some doubts.
I want to add some products to the file, I already have other own brands created. In one I can add an image I want to each product and in the other I can add custom text to each product.

The problem arises when I want to add the Countdown Timer Ultimate shortcode, since it is not displayed, the generated shortcode code itself is displayed: [wpcdt-countdown id=”6369″] , instead of showing me the numbers.

I have also tried to do it with another of your options:

this doesn’t work for me either.

Can you help me to insert the shortcode in my file?

What am I doing wrong ?

* Registramos el Metabox
============================================================================= */

function biogredos_custom_product_metabox(){

  // Memberships Metabox
  add_meta_box( 
      'product-custom-settings', 
      __( 'Producto', 'textdomain' ), 
      'custom_product_callback', 
      'product' 
  );

}
add_action( 'add_meta_boxes', 'biogredos_custom_product_metabox' );


/* Agregamos los campos
============================================================================= */


function custom_product_callback(){

  $screen = get_current_screen();
  if ( $screen->action !== 'add' ) :

      global $post;
      $post_id = $post->ID;

      $logo = get_post_meta( $post_id, 'ct_product_logo', true );
      $texto = get_post_meta( $post_id, 'ct_product_title', true );
      // Countdown Timer Ultimate shortcode
      $descuento = get_post_meta( $post_id, 'ct_product_contando', true );

  else :

      $logo = '';
      $texto =  '';
	  $descuento = '';

  endif;

  // Logo
  echo '<div class="trn-form-control">';
  echo '<div class="trn-row">';
  echo '<div class="trn-col-2"><label>Logo</label></div>';
  echo '<div class="trn-col-10">';
  echo '<input type="text" id="custom-product-logo" name="custom-product-logo" value="' . $logo . '">';
  echo '</div>';
  echo '</div>';
  echo '</div>';

  // Titulo
  echo '<div class="trn-form-control">';
  echo '<div class="trn-row">';
  echo '<div class="trn-col-2"><label>Titulo</label></div>';
  echo '<div class="trn-col-10">';
  echo '<input type="text" id="custom-product-title" name="custom-product-title" value="' . $texto . '">';
  echo '</div>';
  echo '</div>';
  echo '</div>';
	
	
 // Descuento 
// Countdown Timer Ultimate shortcode
  echo '<div class="trn-form-control">';
  echo '<div class="trn-row">';
  echo '<div class="trn-col-2"><label>Shortcode</label></div>';
  echo '<div class="trn-col-10">';
  echo '<input type="text" id="custom-product-contando" name="custom-product-contando" value="' . $descuento . '">';
  echo '</div>';
  echo '</div>';
  echo '</div>';	

}

/* Guardamos los datos
============================================================================= */

function biogredos_product_save_custom( $post_id ) {

  $post_type = get_post_type( $post_id );
  if ( $post_type == 'product' ) :

      $logo  = sanitize_text_field( $_POST['custom-product-logo'] );
      $titulo  = sanitize_text_field( $_POST['custom-product-title'] );
       // Countdown Timer Ultimate shortcode
      $contando = sanitize_text_field( $_POST['custom-product-contando'] );
	
      update_post_meta( $post_id, 'ct_product_logo', $logo );
      update_post_meta( $post_id, 'ct_product_title', $titulo );
      // Countdown Timer Ultimate shortcode
      update_post_meta( $post_id, 'ct_product_contando', $contando );

  endif;

}
add_action( 'save_post', 'biogredos_product_save_custom');


/* Mostramos los datos
============================================================================= */


function biogredos_show_custom_product_data(){

  global $product;
  $post_id = $product->get_id();

  $logo = get_post_meta( $post_id, 'ct_product_logo', true );
  $texto = get_post_meta( $post_id, 'ct_product_title', true );
   // Countdown Timer Ultimate shortcode
  $shortcode = get_post_meta( $post_id, 'ct_product_contando', true );
	
  if ( $logo ) :
      echo '<img class="degradableimage" src="' . $logo . '">';
  endif;

  if ( $texto ) :
      echo '<p class="degradable">'. $texto . '</p>';
  endif;
 
 // Countdown Timer Ultimate shortcode
 if ( $shortcode ) :
      echo '<p class="descuento">'. $shortcode . '</p>';
  endif;	
	
}
add_action( 'woocommerce_after_shop_loop_item_title', 'biogredos_show_custom_product_data' );