Instead of using wp_tag_cloud
pls try this in product page
<?php $terms = get_the_terms( $post->ID , 'city' );
foreach ( $terms as $term ) {
$term_link = get_term_link( $term, 'city' );
if( is_wp_error( $term_link ) )
continue;
echo '<a href="' . $term_link . '">' . $term->name . '</a>';
}
?>