Strange 301 behaviour for URL

Hi Maciej

We need your help with defining the reason for the 301 response from page https://borisstudio.com/kharkov/portfolio/

Results for:

• ?debug_url=1

Array
(
    [uri_parts] => Array
        (
            [lang] => ru
            [uri] => kharkov/portfolio
            [endpoint] => 
            [endpoint_value] => 
        )

    [old_query_vars] => Array
        (
            [attachment] => portfolio
        )

    [new_query_vars] => Array
        (
            [name] => portfolio
            [post_type] => cities
            [cities] => portfolio
            [do_not_redirect] => 1
        )

    [pm_query] => 166887
    [content_type] => Post type: cities
    [version] => 2.3.1
)

• ?debug_redirect=1

Array
(
    [query_vars] => Array
        (
            [name] => portfolio
            [post_type] => cities
            [cities] => portfolio
            [do_not_redirect] => 1
            [error] => 
            [m] => 
            [p] => 0
            [post_parent] => 
            [subpost] => 
            [subpost_id] => 
            [attachment] => 
            [attachment_id] => 0
            [pagename] => portfolio
            [page_id] => 0
            [second] => 
            [minute] => 
            [hour] => 
            [day] => 0
            [monthnum] => 0
            [year] => 0
            [w] => 0
            [category_name] => 
            [tag] => 
            [cat] => 
            [tag_id] => 
            [author] => 
            [author_name] => 
            [feed] => 
            [tb] => 
            [paged] => 0
            [meta_key] => 
            [meta_value] => 
            [preview] => 
            [s] => 
            [sentence] => 
            [title] => 
            [fields] => 
            [menu_order] => 
            [embed] => 
            [category__in] => Array
                (
                )

            [category__not_in] => Array
                (
                )

            [category__and] => Array
                (
                )

            [post__in] => Array
                (
                )

            [post__not_in] => Array
                (
                )

            [post_name__in] => Array
                (
                )

            [tag__in] => Array
                (
                )

            [tag__not_in] => Array
                (
                )

            [tag__and] => Array
                (
                )

            [tag_slug__in] => Array
                (
                )

            [tag_slug__and] => Array
                (
                )

            [post_parent__in] => Array
                (
                )

            [post_parent__not_in] => Array
                (
                )

            [author__in] => Array
                (
                )

            [author__not_in] => Array
                (
                )

            [search_columns] => Array
                (
                )

            [tax_query] => Array
                (
                    [0] => Array
                        (
                            [taxonomy] => language
                            [field] => term_taxonomy_id
                            [terms] => Array
                                (
                                    [0] => 47
                                )

                            [operator] => IN
                        )

                )

            [update_post_term_cache] => 1
            [ignore_sticky_posts] => 
            [suppress_filters] => 
            [cache_results] => 1
            [update_menu_item_cache] => 
            [lazy_load_term_meta] => 1
            [update_post_meta_cache] => 1
            [posts_per_page] => 20
            [nopaging] => 
            [comments_per_page] => 50
            [no_found_rows] => 
            [order] => DESC
        )

    [redirect_url] => -
    [redirect_type] => -
    [queried_object] => WP_Post Object
        (
            [ID] => 166887
            [post_author] => 28
            [post_date] => 2024-06-14 07:59:15
            [post_date_gmt] => 2024-06-14 04:59:15
            [post_content] => <section class="portfolio-block pt-5">
<h2 class="section-title">Наши работы</h2>
<p>[boris_portfolio categories='21940,21944']</p>
</section>
            [post_title] => Наши работы
            [post_excerpt] => 
            [post_status] => publish
            [comment_status] => closed
            [ping_status] => closed
            [post_password] => 
            [post_name] => portfolio
            [to_ping] => 
            [pinged] => 
            [post_modified] => 2024-06-25 17:48:32
            [post_modified_gmt] => 2024-06-25 14:48:32
            [post_content_filtered] => 
            [post_parent] => 0
            [guid] => https://borisstudio.com/?post_type=cities&p=166887
            [menu_order] => 0
            [post_type] => cities
            [post_mime_type] => 
            [comment_count] => 0
            [filter] => raw
        )

)

• ?debug_wp_redirect=1 showing expected page

Thanks in advance for your help!

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