Fatal error when accessing post-sitemap.xml

Hello, Im using your plugin and it works pretty much perfectly, except 1 little problem.

When I try to access my post sitemap – it gives me 500 error.

https://www.coma.lv/sitemap_index.xml

Fatal error: Uncaught TypeError: Argument 2 passed to wp_permastructure::parse_permalinks() must be an instance of WP_Post, instance of stdClass given, called in /home3/coma/public_html/coma.lv/wp-includes/class-wp-hook.php on line 286 and defined in /home3/coma/public_html/coma.lv/wp-content/plugins/wp-permastructure/wp-permastructure.php:244 Stack trace: #0 /home3/coma/public_html/coma.lv/wp-includes/class-wp-hook.php(286): wp_permastructure->parse_permalinks(‘https://www.com…’, Object(stdClass), false) #1 /home3/coma/public_html/coma.lv/wp-includes/plugin.php(203): WP_Hook->apply_filters(‘https://www.com…’, Array) #2 /home3/coma/public_html/coma.lv/wp-includes/link-template.php(240): apply_filters(‘post_link’, ‘https://www.com…’, Object(stdClass), false) #3 /home3/coma/public_html/coma.lv/wp-content/plugins/wordpress-seo/inc/sitemaps/class-post-type-sitemap-provider.php(603): get_permalink(Object(stdClass)) #4 /home3/coma/public_html/coma.lv/wp-content/plugins/wordpress-seo/inc/sitemaps/class-post-type-sitemap-pr in /home3/coma/public_html/coma.lv/wp-content/plugins/wp-permastructure/wp-permastructure.php on line 244

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