It's a cross-domain policy issue. Your website uses a different domain in English than in Finnish, but the font is being loaded from the Finnish domain in both languages. Here's what the browser console says:
Font from origin 'http://pinkkireissaa.com' has been blocked from loading by Cross-Origin Resource Sharing policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://pinktravels.net' is therefore not allowed access.
There are a few different ways you can fix this:
- Load your fonts from the correct domain for each language. That probably means editing your theme.
- Add the aforementioned "Access-Control-Allow-Origin" header for the request to the font files. This means changing configurations on your web server
- Host your fonts on another server entirely, that is properly configured for this kind of usage (Google Fonts, TypeKit, etc.)
- Change your Polylang settings to indicate language in another fashion than by a different domain