no sitemap found

Hi,
We have installed the plugin SEO Yoast, activated it and it seems to work fine. However, as we do not have many traffic, we did some analysis about the sitemap.
The SEO check on these two pages came to the result that there is no sitemap of Soldoona available.

https://seorch.de
https://www.seitenreport.de/

Printscreen of the results:
https://picload.org/view/drropaar/bildschirmfoto2017-10-30um14.4.png.html
https://picload.org/view/drropaaa/bildschirmfoto2017-10-30um14.4.png.html

What do we need to change in order that the test results are successful?

thank you for your feedback
Regards
Philipp

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