I am going crazy with this error. Maybe someone can enlighten me ...
the domain is: compra-mascarillas.com
I am using nginx
When I run the following command: $certbot --nginx
this happens

server is a fresh ubuntu 18 install thank you
On
I have faced the below error while renewing the SSL Certificate with certbort
Failed authorization procedure. sub-domain.com (http-01): urn:ietf:params:acme:error:connection :: The server could not connect to the client to verify the domain :: xxxx: Fetching http://domain-name/.well-known/acme-challenge/xxxxxxxx: Timeout during connect (likely firewall problem)
Open port 80 from all (0.0.0.0/0), and then renew the certificate and it's worked for me. Once renewed close the port.
I have fallen into the same trap of founding mistakes in my Nginx configuration. But after doing a lot of research I have found that my domain service provider(Godaddy in my case) was not properly configured.
Make sure to set proper Type-A setting with a valid IP address of your machine.
An A Record maps a hostname to one or more IP addresses, while the CNAME record maps a hostname to another hostname.