The problem exist only at root / sitemap index
https://sonntagsnachrichten-herne.de/sitemap.xml
the other sides works
https://sonntagsnachrichten-herne.de/sitemap-news.xml
https://sonntagsnachrichten-herne.de/sitemap-posttype-post.2021.xml
https://sonntagsnachrichten-herne.de/sitemap-posttype-post.2022.xml
Chance to “xml-sitemaps-manager” is no solution.
.htaccess is okay there are no changes.
No conflict with other plug-ins I think.
I payed for support and XML Sitemap Advanced but, I cannot change the name of the sitemap index also. ???
