Frontpage > Content not visible? (Menu and Footer are visible)

Hello,

I have updated Enfold to the latest version & updates WP to the latest version.
After this update my page worked well, everything was fine.

But now (a view days later, without working on my page) > the content on the Frontpage is not shown.
I followed your instructions on this topic – but it not resolved my problem.
https://kriesi.at/support/topic/having-problems-after-updating-to-wordpress-4-5-please-read-this-first/

Can you please take a look at this? Because that´s over my wordpress-skills…. :(

I figured out this:
I have the page called “Frontpage” > this is the page set to index page (settings > reading…)
As you can see, the content is not shown :(

For testing I have duplicate the page “Frontpage” and renamed it in “Startseite”
> this page has exactly the same content as my Frontpage.
If you now look at this page in your browser, you can see all content!

Can you maybe check this?
I have no idea, why the page content only not is shown, if I set the page to my index page…
Thank you very much!