kiccokeys

I solved like this (if can be helpful)

//inside the loop
$date = get_post_meta($post->ID, 'event_start_date', true); if($date != ''){echo date("j F Y", strtotime($date));
$time = get_post_meta($post->ID, 'event_start_time', true); if($time != ''){echo date("H:i", strtotime($time));} 
//inside the loop