net::ERR_CERT_COMMON_NAME_INVALID is Chrome telling you that the common name of your SSL certificate for https://analytics.WEBSITE.de is invalid and therefore the browser refuses to connect to it.
Thanks. The error message is gone now. But the data is still not there.
After increasing the time period a little, I noticed that parts of the data seem to be displayed, but only until April 2020. After that, nothing more.