Locales are not returned in API response

I’ve set up another locale beside the default one, but the API endpoint https://cdn.contentful.com/spaces/<space-id> only returns the default locale no matter what I do.

Before you ask, the space ID and access token is the correct one, since the application updates when I change some entry values. The only thing that does not update is the locale.

The locale is enabled in response, and I have also enabled localization on one field in one of the content models, as well as added a localized version of the field in an entry.
However, there is still no locale in the API endpoint, and attempting to retrieve entries with the locale specified results in “Unknown locale: en-US” (the default locale is Swedish, which does work when I specify “sv-SE” as the locale, but not “en-US” which is added to the sape and I made sure it is United States, check the image below)

I also tried adding German, for example, but results in the same behavior.

Furthermore, I tried removing Swedish as the default language and having English as the default instead, and after running the space API endpoint above again, it does not even look like it propagates correctly because it is still using Swedish as the default.

Could there be caching involved here?

I found out that this is because our space currently uses an alias “master -> master-2020-05-05”, but since the API key did not have access to “master-2020-05-05” and only to the alias “master”, the changes in locale did not propagate to the alias.
When giving the API key access to both the alias and the actual environment, the locale updated.

This, to me, sounds like a bug because one would assume that giving access to the alias would also give access to the environment that the alias points to, which it does not seem to do.

Furthermore, after revoking access to the original environment, changing the locale, and checking the response again, nothing is propagated and it is as if nothing changed.
After giving access again, the changes are visible in the response.

This further indicates that thus must be a bug, since it seems like the alias has its own denormalized locales that only update if the API key has access to the environment that the alias points to.