Putting https on sites without activated ssl redirects to first site with activated ssl

It's weird so I don't even know how to put a proper title for it.
ISpconfig is the latest version, Ubuntu 18.04, installed and configure according to the howto. Multiserver setup (2 servers, 1 web and 1 mail).
If I try to add https on a site where SSL is not activated, apache redirects to the first site in alphabetical order that has ssl activated and it wants to use this sites certificate and that throws a warning. Desired behavior would be not to allow that or maybe redirect to a default error page with something like

Code:

Redirect 403 /
ErrorDocument 403 "Not allowed"

I've tried to activate the default-ssl.conf and put this snippet in there, but still same behavior.
You can replicate that behavior by using https://<IP_OF_YOUR_SERVER>. I was able to replicate that on every server with apache2 and ispconfig installed.
Any idea how I could prevent this ?

 

I've tried that,

I've tried that. Didn't work, still uses the certificates of the domain that apache used before. I also activated the ssl-default.conf site. No change. But with the information you gave me I can better search for a solution now. Thanks

 

did you change the name of default-ssl.conf before you activated it?
if not, and your first enabled ssl site starts with a number or A - C or Da - Dee then it's still going to show that first.
disable the default-ssl.conf site, rename default-ssl.conf to 000-default-ssl.conf and then re-enable that site.