If no like, it show all post

Hello
When I click 1 like, it functions well. It only show 1 post.
But if I don’t click at all, It show all post.
I use this code.

$favorites = get_user_favorites();
// Method 1: simple foreach loop
$favorites_query = new WP_Query(array(
‘post_type’ => ‘post’,
‘posts_per_page’ => -1,
‘post__in’ => $favorites
));
if ( $favorites_query->have_posts() ) : while ( $favorites_query->have_posts() ) : $favorites_query->the_post();
get_template_part(‘post’, ‘featuredimage’);
endwhile; endif; wp_reset_postdata();

https://www.ads-software.com/plugins/favorites/