File list of option page do not display in frontend

Hello everyone! How are you?

I always use cmb2 and I never had problems.
The times I used a file list … I did it in a CPT. This time I need to do it in an option page.
I manage to create the metabox in the backend and load the files and that they are saved there.

My problem is when I want to show them in the frontend.

I paste my code, which works correctly in the CPT. So they tell me where I’m wrong if they’re so kind.

Backend:

    // Slider página principal
    $home_options->add_field( array(
        'name' => 'Slider página principal',
        'desc' => 'Agrega las imagenes del slider',
        'id'   => 'slider-principal-fox',
        'type' => 'file_list',
        'preview_size' => array( 100, 100 ), // Default: array( 50, 50 )
        'query_args' => array( 'type' => 'image' ), // Only images attachment
        // Optional, override default text strings
        'text' => array(
            'add_upload_files_text' => 'Añadir o Subir Imagen', // default: "Add or Upload Files"
            'remove_image_text' => 'Eliminar Imagen', // default: "Remove Image"
            'file_text' => 'Imagen:', // default: "File:"
            'file_download_text' => 'Descargar', // default: "Download"
            'remove_text' => 'Eliminar', // default: "Remove"
        ),
    ) );

—

Frontend:

/**
 * Sample template tag function for outputting a cmb2 file_list
 *
 * @param  string  $file_list_meta_key The field meta key. ('wiki_test_file_list')
 * @param  string  $img_size           Size of image to show
 */
function cmb2_output_file_list( $file_list_meta_key, $img_size = 'large' ) {

	// Get the list of files
	$files = get_post_meta( get_the_ID(), $file_list_meta_key, 1 );

	// Loop through them and output an image
	foreach ( (array) $files as $attachment_id => $attachment_url ) {

		echo '<figure>';
		echo wp_get_attachment_image( $attachment_id, $img_size );
		echo '</figure>';
	
	}

}

cmb2_output_file_list( 'slider-principal-fox', 'large' );

Thanks in advance.

Regards!

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