Why excerpt hook not working inside ajax function?

I am using ajax to display more posts.
My ajax function looks like this.

        public function view_more_posts(){
            
            $more_post = new WP_Query(array(
                'post_status'    => 'publish',
                'paged' => $_POST[ 'page' ],
                'posts_per_page' => get_option( 'posts_per_page' )
            ));
            if( $more_post->have_posts() ){
                while( $more_post->have_posts() ){
                    $more_post->the_post();
                        the_title();
                        the_excerpt();
                 }
            }
            wp_reset_postdata();
            die;
        }

add_action( 'wp_ajax_view_more_posts','view_more_posts' );

add_action( 'wp_ajax_nopriv_view_more_posts','view_more_posts');

My problem is that I have customized excerpt_length and excerpt_more but I am not getting customized excerpt. Instead I am getting default excerpt by wordPress.
Why these hook are not working inside ajax?? How I can I get correct excerpt?