There are quite a few clients using that successfully, so it's not
outright broken.
If you can provide a timestamp when you're calling it (accurate to the
second, UTC, please), and the name/callsign you're looking up, I can check
from the logs what is going wrong.
Perhaps there were some accidental extra calls to the API which caused it
to be rate limited, or perhaps the new API implementation is returning the
wrong error code for some other issue. It's new code, it might have bugs.
- Hessu