Customization not working (German stories)

Unfortunately, the customization does not work in any of the German stories. Why is that, or am I doing something wrong?

Steps to reproduce:
On https://chyoa.com/search?type=story&feature=customizable&language=de&sort=last_activity&page=19
Select story
Change first and last name (I have used lower case)
Start over

Behavior: No change.
Expected behavior: Change of character names

 

To use the customization, the story owner needs to set it up and use the respective immersion variables within the story.

E.g. there is a customization

Code:

First Name: John
Last Name: Doe

with the variables being {first_name} and {last_name}, the author needs to write

Code:

{first_name} {last_name} wakes up.

to make customization work.
If they write

Code:

John Doe wakes up.

any changes to the variables in the customization tab won't affect the names in the sentence.

So only the respective authors of the stories can fix this issue.

(Note: First Name: John and Last Name: Doe are the default values when the option is activated. Some story owners might have done that by accident.)