Why it matters
Listing a URL in the sitemap says "index this"; noindex, a robots block or a canonical pointing elsewhere contradict it.
How to fix it
Only include self-canonical, indexable URLs; exclude app, auth and filter routes.
References
More seo rules
void seo reports 60 rules in this category. What search engines need from the raw response: status codes, titles and descriptions in <head>, self-referencing canonicals, one h1, crawlable links, Open Graph, icons, robots.txt and a sitemap with real dates.
robots-sitemap-directiverobots.txt has no absolute Sitemap: linesitemap-missingNo reachable sitemapsitemap-invalidSitemap isn't valid sitemap XML or exceeds protocol limitssitemap-url-invalidSitemap <loc> is relative or on another hostsitemap-lastmod<lastmod> invalid, in the future, or identical across entriessitemap-url-statusSitemap lists URLs that don't return 200 directlyduplicate-titleMultiple pages share the same <title>duplicate-descriptionMultiple pages share the same meta description