How to set custom post type field as post title to avoid ‘Auto Draft’

I have a custom post type called artists, I combine the artist acf field of first_name and last_name and set that as the title. 

// Auto-populate artist post type title with ACF first name last name.
function nd_update_postdata( $value, $post_id, $field ) {
// If this isn't an 'artists' post type, don't update it.
if ( get_post_type( $post_id ) == 'artists' ) {   
    $first_name = get_field('first_name', $post_id);
    $last_name = get_field('last_name', $post_id);
    $title = $first_name . ' ' . $last_name;
    $slug = sanitize_title( $title );
    $postdata = array(
         'ID'      => $post_id,
         'post_title'  => $title,
         'post_type'   => 'artists',
         'post_name'   => $slug
    );
wp_update_post( $postdata, true );
return $value;
}
}
add_filter('acf/update_value/name=first_name', 'nd_update_postdata', 
10, 3);
add_filter('acf/update_value/name=last_name', 'nd_update_postdata', 10, 
3);

https://stackoverflow.com/questions/38857164/how-to-set-custom-post-type-field-as-post-title-to-avoid-auto-draft/50095929#50095929

Generate WordPress Post Tittle from ACF Fields
https://stackoverflow.com/questions/71565994/generate-wordpress-post-tittle-from-acf-fields

//Create new title based on ACF Fields
function update_contacts_title( $value, $post_id, $field ) {
    
    $first_name = get_field('first_name', $post_id). ' ' . $value;
    $last_name = get_field('last_name', $post_id). ' ' . $value;
    //$title = $first_name .' - '. $last_name;
    $title = $first_name;

    $slug = sanitize_title( $title );

    $postdata = array(
        'ID'          => $post_id,
        'post_title'  => $title,
        'post_type'   => 'contacts',
        'post_name'   => $slug
);

    wp_update_post( $postdata );
    return $value;
    
}
add_filter('acf/update_value/name=first_name', 'update_contacts_title', 10, 3);
//add_filter('acf/update_value/name=last_name', 'update_contacts_title', 10, 3);