Domain not resolving as per redirect

I have configured my Sites-->Domain Redirect-->SEO Redirect as www.mydomain.tld => domain.tld and http to https.
However, www is resolving to default Apache page (not the default ISPConfig page as there is no index.html). Http to Https is resolving correctly. Any idea what could be wrong. It's a WordPress site with .htaccess as had to set few 301 redirects from the earlier site.

https://mydomain.tld => perfectly fine
mydomain.tld --> https://mydomain.tld => perfefectly fine
https://www.mydomain.tld --> https://mydomain.tld => perfectly fine
www.mydomain.tld--> default apache page
http://www.mydomain.tld --> default apache page

 

You have to select :
Auto-subdomain : www.
to make the redirection from www.domain.tld => domain.tld working.
Nicolas