Now I found it. I am such a low-tech...
I tried to change the formatting of my TOC and change the language definition in the formatting settings. But still when I open the TOC dialog, the automatic table suggestion are displayed RTL instead of LTR as you can see in the attached screen-shot (finally
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The left attachment displays how it appears in my problematic document.
The right attachment displays how it appears in most of my documents and how it should appear