Most of the visitors to my site are supposed to come from external link with URL my-seite.com/en/var from Facebook ads but Google Analytics shows that most of the landing page is my-site.com/var without en which is the prefix for English version of my site. Am I missing something to configure Google Analytics ? or Facebook has sending the visitors to the wrong URL (by the preview page of the Facebbok ads the URL is set correct with the prefix en)?

Any advise are appreciated.

Thanks.