ISPconfig 3.1 + Nextcloud 13 - how to add a Lets Encrypt certificate to a subdomain?

Question

linux

How to add a Lets Encrypt certificate if Nextcloud 13 should open from a subdomain?
When creating a subdomain, it does not work, it opens the root site of the domain (Wordpress).
When creating a domain alias, the same song.
I will not understand how certificates for a subdomain are created, without creating the subdomain itself. Maybe this is done through the console, but you can’t create it through the panel itself.
Completely confused.
here is the apache config

<VirtualHost *:80>
   ServerAdmin [email protected]
   ServerName cloud.xxxxxxxx.ru


   RewriteEngine On
   RewriteCond %{HTTPS} off
   RewriteRule ^(.*)$ https://%{HTTP_HOST}$1 [R=301,L]
</VirtualHost>



<VirtualHost *:443>
     ServerAdmin [email protected]
     ServerName cloud.xxxxxxx.ru
     DocumentRoot /var/www/nextcloud/

     <Directory /var/www/nextcloud/>
       Options +FollowSymlinks
       AllowOverride All

      <IfModule mod_dav.c>
        Dav off
      </IfModule>

       SetEnv HOME /var/www/nextcloud
       SetEnv HTTP_HOME /var/www/nextcloud

     </Directory>

     <IfModule mod_headers.c>
          Header always set Strict-Transport-Security "max-age=15768000; preload"
     </IfModule>
</VirtualHost>

Answer 1

i.e. your question sounds like this - how to create a certificate for something that does not exist?