add_action( 'wpf_user_created', 'add_group_access_after_registration', 20, 3 );

function add_group_access_after_registration( $user_id, $contact_id, $post_data  ) {
    $ld_groups = array(1286);

    foreach($ld_groups as $group_id) {
        $settings = get_post_meta( $group_id, 'wpf-settings-learndash', true );
        if ( !empty( $settings ) && !empty( $settings['tag_link'] ) ) {
            wp_fusion()->user->apply_tags( $settings['tag_link'], $user_id );
        }
    }
}