show posts under custom post type with same autj

You can you this code to show posts based on user:

$args = array(
'author'        =>  $user_id,
'orderby'       =>  'post_date',
'order'         =>  'ASC',
'posts_per_page' => 1
);

$query = new WP_Query( $args );

if ( $query->have_posts() ) {
    while ( $query->have_posts() ) {
        $query->the_post();
    }
}
wp_reset_postdata();