Subdomain pointing folder not working as subdomain

Hi.
I have an installation of wordpress on a folder within my domain: https://ticiero.com/no/

I also have a subdomain no.ticiero.com which points to the folder /no

So, my problem now is that going to no.ticiero.com loads an error page saying the Page Not Found. Clearly, I messed up with the installation since the blog page is only visible at https://ticiero.com/no which is not what I wanted.

How can I change the settings so the wordpress installation will be visible from the subdomain (no.ticiero.com) and not from the subfolder (ticiero.com/no)? Do I need to change settings in the functions.php, index.php, or wp-config.php files? I assume all the tables can stay the same, is this right?

I would appreciate any guidance.

Thanks!