Why is Wordpress displaying Open Sans without Cyrillic?

Question

CMS

For authorized users (for me, as an admin in particular), the font is displayed validly, with Cyrillic support (that is, Russian letters look good). However, if you go to the site through private mode, or simply log out, Open Sans turns into a different font. That is, roughly speaking, the topic for some reason stubbornly does not want to display Open Sans (Cyrillic characters) validly for everyone except the administrator. Website: nikonov.info (I installed this template just yesterday, in other theme settings it was possible to specify Cyrillic support in Open Sans, but in this theme there is no such setting, only the font)

Answer 1

Is the font connected in the theme? Is there an appropriate css?
UPD: In your head, a font from Google is connected only with Latin.
subset=latin,latin-ext

Answer 2

Instead of looking, maybe a valid font is not set for ordinary users?

Answer 3

Give me a link to the site or something! Maybe DOCTYPE is not specified? For I had one such case, when I am an admin, then everything is OK, and when a user, the design is a little mowed down. It turned out that the problem was in the doctype