Sitemap_Index.xml is Throwing a 404 Error

Hello,

Hello,
Why the Sitemap_Index.xml is Throwing a 404 Error Even though I check all the headings on your page, I continue to receive the Sitemap_Index.xml page not found error.

I uninstalled the plugin and reinstalled it, but the problem was not resolved. I just set up the site and have never encountered such a problem before.

If I send you the access information to the site, can you check it for me, where am I doing wrong?

Thanks.