Core Sitemap or Plugin Sitemap
Compare plugin sitemap and current permalink. An old sitemap cache should not point further to the previous address after the correction.
Using robots.txt and the delivered XML file, determine the active sitemap producer. WordPress Core and SEO plugins can select different content and taxonomies. Exclusions belong in this source and not in a downloaded XML copy.
Where to check the setting in WordPress
Go to /wp-sitemap.xml if the core sitemap is used. With an SEO plugin, you determine its sitemap index via robots.txt instead. Check whether the affected content is published and contained in the selected content type or taxonomy.
Example of this specific finding
Illustrative control case: The sitemap calls /performance-alt/, which redirects to /performance/ permanently. The generator uses an outdated URL source.
follow-up audit in WordPress
Review a published paper, a draft and a relevant taxonomy. After a change, retrieve the sitemap index and the affected partial sitemap without logged in session.
Take the final desired address directly into the sitemap and test the regular rebuild. Appropriately pass forwarding for old calls.
Derogations and scope
Do not remove the working redirect, just so that the old sitemap URL returns 200.
Related: WordPress with classic or block theme. SEO plugins and page builders are different; there is no universal menu path for all installations.
Classify the general error
Definition, system-independent causes and further correction examples: The sitemap should specify the desired destination address