A test authorization for www.itanhaem.sp.gov.br to the Let's Encrypt staging service has revealed issues that may prevent any certificate for this domain being issued.
DNS problem: SERVFAIL looking up A for www.itanhaem.sp.gov.br - the domain's nameservers may be malfunctioning; DNS problem: SERVFAIL looking up AAAA for www.itanhaem.sp.gov.br - the domain's nameservers may be malfunctioning
The domain www.itanhaem.sp.gov.br is being served through Cloudflare CDN. Any Let's Encrypt certificate installed on the origin server will only encrypt traffic between the server and Cloudflare. It is strongly recommended that the SSL option 'Full SSL (strict)' be enabled.
https://support.cloudflare.com/hc/en-us/articles/200170416-What-do-the-SSL-options-mean-