Custom post type archive page blank

You have to tell WP that archive.php should apply to your custom post type as well as it’s other defaults. You can use pre_get_posts filter to do this, be sure to research this well before using it as there is a right and wrong way to use this filter.

For example, try:

function add_custom_post_type_to_archiving( $query ) {
    $query->set( 'post_type', array(
     'post', 'custom_post_type_name1','custom_post_type_name2'
        ));
    return $query;
}
add_filter( 'pre_get_posts', 'add_custom_post_type_to_archiving' );