[Geschlossen] WPML cannot conect to wpml.org

Background of the issue:
I am trying to connect the website to my WPML account. The issue can be seen at the following link: versteckter Link.

Symptoms:
WPML cannot connect to wpml.org.
Unable to register: Site key not matching

Questions:
Why can't WPML connect to wpml.org?
How can I successfully connect my website to my WPML account?