How to overcome a cyclic redirect on the main page when the CNC is turned on?

Question

CMS

So, there is a freshly installed WordPress 4.9.8–ru_RU.
One page is written, it is displayed on the main page, everything works.
I go to the "Permalink Settings" item, set any item other than the default one - and a cyclic redirect appears on the main page. At the same time, everything is fine on the rest of the pages.
What I tried:
reinstalled CMS in the "Updates" section;
changed the subject;
disabled all plugins;
created another page, set its output to the main one;
put .htaccess from another site;
None of this helped.
If you set the option "Display on the main page - your latest posts", then the redirect disappears. But you need to display a static page on the main page.
UPD: I did not find smart solutions, demolished wp, reinstalled, the problem disappeared

Answer 1

I did not find smart solutions, demolished wp, reinstalled, the problem disappeared

Answer 2

You haven't provided any source code, and therefore it's hard to say anything.
1) the name of the static home page template should be front-page.php
2) provide the source code for this template