Sitemap lists a URL that does not return 200
What this means
A sitemap is a statement that these URLs are worth crawling. Listing an address that answers 404 or 500 contradicts that, wastes crawl budget on a dead end, and erodes the trust Google places in the rest of the file.
How to fix it
Remove dead URLs from the sitemap, or restore the pages. Generate the file from the same source of truth that decides what is published, so the two cannot drift apart.
Fix effort
This check needs a developer fix: it turns on a routing, hosting or infrastructure decision that no automatic edit can make safely.
Authoritative source
https://developers.google.com/search/docs/crawling-indexing/sitemaps/build-sitemap
Find every page this affects
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