No Comment Fields when Homepage displays a static page

Hi everybody.

I want my Blog to appear not on the Homepage but on a separate Posts Page.
For that reason I defined on the settings/reading Page ‘Your homepage displays’ Then I selected a Home Page and a Posts Page. This works quite well but the comment fields are not displayed on the Posts Page.

When I change this setting that the posts are shown on the Homepage everything works fine.

How can I display my Blog on a separate Posts Page AND have Comment functionality?

I use Theme Twenty Seventeen.

Thx

Wolfgang

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