Cannot get custom fields to display on a taxonomy page

Hello,

I have created a taxonomy called "authors" with the MB Custom Taxonomy plugin and added terms "Agathe Christie" and "Mark Twain". Then with the MB Builder I created some custom fields (country, age) for the authors taxonomy. Then with the help of the MB Term Meta plugin I made those custom fields to appear in the taxonomy term (Agathe Christie and Mark Twain) edit screen. I also created a file "taxonomy-authors.php" in my theme's root. Now the question is how can I display those custom fields values (country and age) on this taxonomy page? I tried all the methods in the documentation (rwbm_meta, rwbm_get_field etc) but cannot display any data:

$term_id = get_queried_object_id();
$value = rwmb_meta( $field_id, array( 'object_type' => 'term' ), $term_id );
echo $value;

Kind regards,
Toomas