Certbot failed to authenticate some domains (authenticator: nginx). The Certificate Authority reported these problems:
Detail: DNS problem: SERVFAIL looking up A for hf20959fw5f.sn.mynetname.net - the domain's nameservers may be malfunctioning; DNS problem: SERVFAIL looking up AAAA for hf20959fw5f.sn.mynetname.net - the domain's nameservers may be malfunctioning
Hint: The Certificate Authority failed to verify the temporary nginx configuration changes made by Certbot. Ensure the listed domains point to this nginx server and that it is accessible from the internet.
Some challenges have failed.
Ask for help or search for solutions at https://community.letsencrypt.org. See the logfile /var/log/letsencrypt/letsencrypt.log or re-run Certbot with -v for more details.
Please how can I solve this issue ?