Symfony locale on homepage issue

Question

my website url's should be:
http://www.example.com/nl
http://www.example.com/en

I set it this way in my config/routes.yml

homepage:
    resource: '@ProjectBaseBundle/Resources/config/routing.yml'
    prefix: /{_locale}

The issue persist when i visit

http://www.example.com/
Without a language. When this happens i got a 404

How to handle it the correct way?

I googled arround, created extra route on the / etc.. The meaning is when they visit the unlocalized adress they get a redirect to the localized homepage.

Tips ?