add_action('pre_get_posts',function($q){if (is_admin() || ! $q->is_main_query()) return;// IMPORTANT:use the taxonomy KEY (not the pretty URL slug). // On your site it's very likely 'resources_category'.
    if ( is_tax('resources_category') ) {
        $term_id = get_queried_object_id();

        // Make sure we only query the Resources CPT and the current term
        $q->set('post_type', array('resources'));
        $q->set('tax_query', array(array(
            'taxonomy' => 'resources_category',
            'field'    => 'term_id',
            'terms'=>array($term_id),)))}},999);