- Issue created by @fkildoo
Sitemaps ping is deprecated for Google. Submitting the sitemap to Google via ping will now give a 404 response. See https://developers.google.com/search/blog/2023/06/sitemaps-lastmod-ping.
Check Google under "submit the sitemap to the following engines" on the settings page (/admin/config/search/xmlsitemap/engines), run cron, and then check for an alert in the Drupal log.
Remove the check box for Google search engine submission on the settings page. Since this was the last option, maybe remove the entire tab/section for Search Engines or add suggested ways to submit sitemaps (through robots.txt and Search Console).