Custom SSL certificates are no longer supported for free subdomains. All free subdomains have SSL by default.
Other Information
I had a SSL certificate on my website for like 6months (renew it once 90 days ago), and now i cant actually renew it again. I can’t find any other way to have the SSL certificate on my website…
Remove the www part from your domain, subdomains of free subdomains are no longer supported. Once you do that, SSL will be managed automatically for you.
You should start promoting the https://madalenatomaz2025.great-site.net URL instead of https://www.madalenatomaz2025.great-site.net so visitors will never see that warning in the first place.