Pihole DNS not adding www on redirects?

I have Pihole up and running as my DNS server on my network. Now I have the following issue:
I open a web browser, for example chromium. In the address bar I type a site that I have never visited before like this:

dn.se
and hit enter

The browser now goes to

https://dn.se/
Which is broken because it actually needs the www part, like this:

https://www.dn.se/

I then took my phone, disabled wifi and used the mobile network and setup hotspot and thus my ISP dns and connected my laptop. Typed dn.se and it redirected me to https://www.dn.se/ which is correct.

How can I achieve this redirect with the pi? Is there some configuration on it or the router perhaps?

Pi-hole isn't involved in URL rewriting.
Your browser is responsible for manipulating URLs.

Hmm then its some bad configuration on my router perhaps?

I just tested opening MS edge (which I never used) on both my laptop and desktop. My laptop connected to mobile hotspot and desktop to my own network. typed dn.se in both and laptop was directed with www but not my desktop.

No, it's your browser.

Hmm ok, its just odd because it happens in all my browser, edge, chrome, ff on my desktop and brave on my android phone.

Heck, if I connect to my wifi, type an adress, it fails, connect to wifi, it works.

Edit: This can be closed, the solution was to forward all nds requests like this: