Post List by category and under custom taxonomy

Your post list is repeating because in your WP_Query args you are fetching posts just from the category with ID “2”.

In order to get posts from custom taxonomies you need to use a tax_query inside your WP_Query. You can read more about tax_query here:
https://developer.wordpress.org/reference/classes/wp_query/#taxonomy-parameters

I would do the following:

$args = array(
    'post_type' => 'post',
    'tax_query' => array(
        'relation' => 'OR',
        array(
            'taxonomy' => 'category',
            'field'    => 'term_id',
            'terms'    =>  2,//Your WordPress category here
        ),
        array(
            'taxonomy' => 'tutorial',
            'field'    => 'term_id',
            'terms'    =>  $taxonomy->term_id,
        ),
    ),
);
$query = new WP_Query( $args );