ssl_issuer_unknown when connecting only to a certain <VirtualHost> with apache

Question

I've this problem with my site configuration and ssl certificates. I've got two websites on the same machine running two different domains. Their respective ssl certificate is issued by Cloudflare and stored in the /ssl folder of my machine, which by the way, it owned by the www-data group, just to be sure that the content of the files inside are readable 100% by the apache webserver. Then I've got all the websites on /var/www, which is also owned by www-data etc. etc. The point is that in the configuration, basically every websites and virtualhost handles correctly the ssl certificate, even the stupid webdav does. But one of the two domains just straight up wont work with his ssl certificate. The funny thing is that only that certain virtualhost behaves in the wrong way, because other virtualhosts on the same domain, but with different subdomains, they work just fine. Down here below i leave my sites.conf, just a snippet of it at least.

<VirtualHost *:443>
  ServerName redacted.dev
  
  SSLEngine on
  SSLCertificateFile /ssl/redacted.cert.pem
  SSLCertificateKeyFile /ssl/redacted.private.key

  DocumentRoot /var/www/sito
</VirtualHost>

<VirtualHost *:443>
  ServerName files.redacted.dev
  
  SSLEngine on
  SSLCertificateFile /ssl/redacted.cert.pem
  SSLCertificateKeyFile /ssl/redacted.private.key

  DocumentRoot /var/www/files

  <Directory /var/www/files>
    AllowOverride none
    Require all granted
    Options +Indexes -FollowSymLinks -MultiViews
  </Directory>
</VirtualHost>

Here's the error given by my browser (I've tried with others but same result)

Browser error

What should I do in order to fix this SSL issue?

Answer 1

Update, the site started working without me doing anything at all.

I still don't know what the issue was.