ACF query-pass field value

SOLUTION:

$posts = get_field('choose_office'); if( $posts ): 
 foreach(array_slice($posts, 0, 1) as $post):
  setup_postdata($post);
  $post_ID =  get_the_ID();
   endforeach; 
   wp_reset_postdata();
   endif;

  $args = array(


'meta_query' => array(

        array(

'key' => 'office', // name of custom field-post object
'value' => $post_ID, //name of relationship field
'compare' => 'LIKE'
                            ),

                        ),  
    );

Solution from question:
https://stackoverflow.com/questions/46816190/using-post-id-inside-reverse-acf-relationship-querie