ACF: get post order by date picker

gistfile1.txt

<?php $news = get_posts(array(
                        'post_type' =>  'post',
                        'post_status' => 'publish',
                        'meta_key' => 'data_evento', //nome custom field
                        'orderby' => 'meta_value_num',
                        'order' => 'DESC',
                        'posts_per_page' => 12,
                        'cat' => '3'
)); ?>

<?php foreach($news as $nw): ?>