When I click to edit a web domain (pointing on the serveur for several month) and try to add a Lets Encrypt SSL certificate, I have this message : “Error: DNS record for www.yoursite.com doesn’t exist”. Sure, for this domain, I have let the registar use his own DNS and not Hestia.
To try solving this bug, I have delete the domain and recreate it and I have rebuild all site/dns/mail.
Solved. You give me the idea to check again the DNS to my registar. I had forget to put the www entry again after a reset I had done on the domain name.