Changed ACF in admin area to “Post Object” and then use;
<?php
$terms = get_sub_field('category');
if( $terms ):
?>
<ul>
<?php foreach( $terms as $term ): ?>
<h2>Term: <?php echo esc_html( $term->term_id ); ?></h2>
<?php endforeach; ?>
</ul>
<?php endif; ?>
