Due to an issue in the issue collector (that's another topic), the created issues are always assigned to the default author.
I tried to change the author to the correct one, which seemed to work, but in fact it doesn't.
The default customer is called dummy. As you can see, the author is (seemingly) set to "test".

But in fact the user doesn't get any updates. I tried to add a comment - the user doesn't receive an email.
Then I checked the helpdesk for the user. When the user is the author, he should see his issue, shouldn't he?

In fact there is only an issue, which I created using that interface. But number 10 is not visible.
Any idea, what's wrong here? How can I change the author, so that the customer gets the updates and can participate (by addings comments)?
Jira Core is version 8.21.1
Jira Service Management is version 4.21.1