Raubotter

Hello everyone, this is my first post here.
I have a problem, and a forum search didn't bring me the solution.

In mainmenu, i have a "Table - Content Section" link. This brings up a page with description about the section and a list of categories in this section. And here is the problem: only 6 (of currently 8) categories are listed.
Weird: when i click on such a category link, it brings up the table with the content (as it shoud) AND A LIST OF THE OTHER CATEGORIES BELOW, in which ALL 8 CATEGORIES are listed...

How to display all category links on section page? I tried every option i found, and i also looked into "com_content" php files, but i am a beginner in php...

I hope someone here can help me. Thanks in advance!