How to loop through an array with category names strings to display posts?

Hi

A pmpro_getMembershipCategories($current_user->ID); function returns an array of names of categories. The names are only simple strings like CategoryName – and nothing more I think.

array(1) {
[0]=>
string(2) “14”
}

How to loop through it and display posts that are inside of each category?

This code doesn’t work:

if (true) {
    $args = pmpro_getMembershipCategories($current_user->ID);
    $query = new WP_Query($args);

    if ($query->have_posts()) {
        while ($query->have_posts()) {
            $query->the_post();
            ?>
            <a href="<?php the_permalink(); ?>"><?php the_title(); ?></a>
            <?php
        }
        wp_reset_postdata();
    }
}

Any hints?

Regards!