Error 403 with specified app_id and app_key

I’ve been struggling with this simple thing for a couple of hours for now.
The thing is that I get error 403 and an HTML page with reCaptcha instead of proper response, even though I’ve added app_id and app_key to the query string. This happens even in Postman’s collection provided by TfL :frowning:
final query looks like this:<my_app_id_here>&app_key=<my_app_key_here>

Has anybody encountered this odd behaviour? Any ideas for workaround?

Figured it out: turns out it was because of non-UK location