trouble using xili-language with a website url different from the wordpress url

Hi there,

I am using xili-language to have four language versions on this page:
https://vision.wettintv.de (WordPress address)

I want to use the domain https://www.vision-videoschool.eu as website address for the blog.
(It is just forwarding to https://vision.wettintv.de via another server where it was registered. Forwarding is working.)

But when I define it in the settings as the website address, switching between different language versions is not working anymore.

May I have to define something for the xili-labguage plugin seperately?

Thx in advance!