Why doesn't the browser load Cyrillic font-face fonts?

Question

HTML

There is a font Fira Sans. I connect it to css via font-face. When I enter information, headings, anything in Latin, the browser displays this code in the desired font, but if I write Cyrillic, it simply makes the font standard for the browser. At the same time, the font itself supports Cyrillic. I downloaded via fontsquierrel and checked the Cyrillic spelling there. Help, who knows what could be the problem? I’ve been importing for several hours, with PT Sans the same

Answer 1

With standard settings, the protein cuts the Cyrillic alphabet. Choose expert mode -> custom subsettings -> desired languages.

Answer 2

show connection code