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The anti-spam proof was already used

Error code pow_challenge_used
Anti-spam and limits

The anti-spam proof was already used

pow_challenge_used

The proof-of-work challenge can only be spent once.

HTTP 409·Anti-spam and limits

What it means

What happened

The proof-of-work challenge can only be spent once.

Why

Why it might have happened

  • The publish request may have been submitted twice.
  • A tool may have retried with the same proof.
Next steps

What you can try

  1. Try publishing again so a new proof is created.
  2. Avoid double-clicking or retrying the same request manually.
  3. Update the tool if it keeps reusing proofs.
Related
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