Thanks, that was very helpful. Just to be precise and for those who will find this post useful. The_field prints out clean html so the right way will be:
foreach($product_terms as $term){ $category_id_tag = 'post_tag_'.$term->term_id;
echo '<a href="'.get_term_link($term->slug, 'post_tag').'" title="';
the_field('title_page', $category_id_tag); echo '"><span>'.$term->name.'</span>
<span>'.$tag_title.'</span>
</a> ';
}
Finally, I’ve found an answer. Not sure if it’s specific in my case or it’s a general WP issue but default value for posts per page set up in WP admin (General > Reading > Maximum number of posts per page) should be less than value for posts_per_page parameter for custom query. In my case, I’ve changed in WP options value to 3 and for other page changed this to 5 and all working fine now!
