Can't access nominatim API via Chrome

Hello! I get strange 403 responses from nimonatim API when sending requests from Chrome.
I’m trying to develop web app that is using OSM data to draw city boundaries. Requests are being send from users’ browser via js, but it doesn’t work in Chrome on Windows 10.
If I manualy send request from Chrome, I get 403 response with usage policy violation message, but same request from postman or IE (from same host) works. As far as I understood policy, I’m sending requests as an “end-user” and definitely not faster than 1 rps.
What am I doing wrong?

Please make sure you send a referrer with your requests.

Also, please consider if you are using the right tool. Nominatim is a geocoding service, not a boundary geometry downloader. Make sure that the requests are rare enough that over all your clients, you don’t send more than 1 request/s. Make heavy use of caching on your server-side.