Polylang changes content based on browser but does not change RUL

Hi Chouby! ??

Using the 1.4 version with WP 3.8.1
I’ve checked the option that detects user browser, in order to redirect them to the adequate language.
Language switching works – but domain is not redirected.

Domains:
EN: https://en.fitforlife.fr
FR: https://www.fitforlife.fr

My browser is in english, if I type https://www.fitforlife.fr, the content being served is in english (ok) but I am not redirected to en.fitforlife.fr – instead the URL remains.

If I type en.fitforlife.fr, the content being served is in english (ok)

thank you!

https://www.ads-software.com/plugins/polylang/