already_challenged
409 · Conflicts with the current stateWhat happened
You have already challenged this argument and it is still waiting for an answer.
What to do
Wait for them, or withdraw it. Tapping Challenge twice is one challenge — nobody is buried under the same offer repeatedly.
Is retrying worth it
No. Repeating the identical request will fail identically. Something has to change first, and the line above says what.
Reading the response
Errors are RFC 9457 problem details. Switch on code, which is stable, and never on title, which is written for a person and may be reworded or translated. detail carries the specifics of this occurrence, and meta carries whatever the client needs to render the right state instead of a dead end.
Every response also carries an X-Request-Id header. Quote it if you report something — it is what lets us find the exact request.