Time out when creating certificate

[AlexCastino]

time out when creating certificate
I have my domain pointed to a machine with Ubuntu 20.4 with nginx and node, when I try to run the command to create the certificate, certbot creates the file in the directory, I can access the file through the browser before it is deleted by certbot
but it returns me in the certbot timeout
Certbot failed to authenticate some domains (authenticator: webroot). The Certificate Authority reported these problems:
Domain: backend.pulsechat.com.br
Type: connection
Detail: 179.34.51.195: Fetching http://backend.pulsechat.com.br/.well-known/acme-challenge/9Axq8xuVJ7o8FT7SuXuRMYNCDAzhvIk_1GbGDFQGLOQ: Timeout during connect (likely firewall problem)

I don't know what to do anymore, I disabled the server's firewall, pointed out ports on the modem (443,80,25,8080 etc)
Any light on what I can do?
Command I ran (test mode):
sudo certbot Certonly --dry-run --webroot -w /etc/certificados/ -d backend.pulsechat.com.br -d pulsechat.com.br

[MikeMcQ]

Have you tried accessing your domain from the public internet?

Because I can't see it from my own USA-based server. The Let's Debug test site (https://letsdebug.net) cannot see it. And of course Let's Encrypt itself cannot.

This means that either no one can access your site from the public internet. Or, maybe you have a firewall blocking access outside your region or country.

Try a mobile phone with wifi disabled when you check if the challenge file exists.

Try adding these options to your command to give you more time to check the file

sudo certbot Certonly --debug-challenges -v --dry-run --webroot -w /etc/certificados/ -d backend.pulsechat.com.br -d pulsechat.com.br