Copy custom field value to post title

Okay! Finally, I was able to make it work. Below is the complete working code.

add_filter( 'wp_insert_post_data' , 'modify_post_title' , '99', 2 ); // Grabs the inserted post data so you can modify it.

function modify_post_title( $data )
{
  if($data['post_type'] == 'artist' && isset($_POST['acf']['field_573676a95d920'])) { // If the actual field name of the rating date is different, you'll have to update this.
    $ArtistName = $_POST['acf']['field_573676a95d920'];
    $data['post_title'] =  $ArtistName ; //Updates the post title to your new title.
  }
  return $data; // Returns the modified data.
}

//Save ACF field as post_title for front-end
add_action('acf/save_post', 'change_artist_title_frontend');

function change_artist_title_frontend($post_id) {
    global $_POST;
    if('artist'== get_post_type())
    {
        $post_custom_title = $_POST['acf']['field_573676a95d920'];
        $my_post = array();
                $my_post['ID'] = $post_id;
                $my_post['post_title'] = $post_custom_title;
remove_action('acf/save_post', 'change_artist_title_frontend');
                    wp_update_post( $my_post );
add_action('acf/save_post', 'change_artist_title_frontend');
    } 
}