Hint: The Certificate Authority failed to download the temporary challenge files created by Certbot. Ensure that the listed domains serve their content from the provided --webroot-path/-w and that files created there can be downloaded from the internet.
Some challenges have failed.
Ask for help or search for solutions at https://community.letsencrypt.org. See the logfile /home/frappe/.certbot/logs/letsencrypt.log or re-run Certbot with -v for more details.
Reload the Nginx configuration (service nginx reload).
Go to the TLS Certificate for the custom domain that fails.
Click Obtain Certificate.
Wait a little bit.
On failure, look at the error log for a TLS Certificate Exception, and look at the connection Detail Type: connection\n Detail: IP ADDRESS and check that the IP is that of the Frappe Press instance. If not, maybe the DNS records are not yet propagated.