Wp-admin language redirect issue

Hi,
I just moved a functioning WP site from Apache to Nginx and it works great. I’m using the latest Q-Translate X with five HTTPS enabled per-domain sites running on five public IPs. (COM/NO/DK/SV/IS/DK)
On Apache this worked great, except that it was a bit slow. That’s why I changed to Nginx.

English is the default language.
BUT now, when you are logged into WP-Admin and select another language from the top-right Language Select flag-list, you get a link like https://www.domain.com/wp-admin/edit.php?post_type=page&lang=no

But then it tries to redirect to the domain too, not just change the backend language: https://www.domain.no/wp-admin/edit.php?post_type=page&lang=no

This makes the user log out and and then the user can’t log back in until you delete the qtranslate cookies or manually add ?lang=en after the wp-admin URL.

With Apache, the WP-Admin URL never changes when you select the other language, so this is probably an NGinx issue?

TLDR;
It doesn’t work to select another language when you’re logged into WP-Admin, it tries to redirect the entire URL. I just want the main .com WP-Admin URL to stay the same and not change, like it used to before with Apache.

Any ideas?

Thanks!

Willy T. Koch
Norway