sitemap_index.xml missing or not detected

Hello!

According to online.seranking my XML file is missing, but I’m using Yoast SEO so I guess it should be added automatically.

What I’ve seen is that when you try to go to https://www.gameszane.com/sitemap_index.xml/ you are redirected to https://www.gameszane.com.

I don’t know if that could be the issue.
What can I do?

Thank you in advance.
Regards.

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