Not properly set up to resolve /.well-known

Nextcloud version: 18.0.7
Operating system and version: Raspbian 10 (buster)
Apache version: Apache 2.4.38
PHP version: 7.3

The issue:
In my admin overview page, it says:

  • Your web server is not properly set up to resolve “/.well-known/caldav”. Further information can be found in the documentation.
  • Your web server is not properly set up to resolve “/.well-known/carddav”. Further information can be found in the documentation.

My Apache2 document root is in /var/www/html
My Nextcloud installation is in /var/www/nextcloud

I created .htaccess in /var/www/html and pasted:

RewriteEngine on RewriteRule ^\.well-known/host-meta /var/www/nextcloud/public.php?service=host-meta [QSA,L] RewriteRule ^\.well-known/host-meta\.json /var/www/nextcloud/public.php?service=host-meta-json [QSA,L] RewriteRule ^\.well-known/webfinger /var/www/nextcloud/public.php?service=webfinger [QSA,L] RewriteRule ^\.well-known/carddav /var/www/nextcloud/remote.php/dav/ [R=301,L] RewriteRule ^\.well-known/caldav /var/www/nextcloud/remote.php/dav/ [R=301,L]

But the error message on my admin panel remains.

What is the correct place to create or edit the .htaccess file?