401: Unauthorized
Likely cause
The origin/application requires authentication that wasn't provided or has expired.
Check
Confirm whether the required credentials (session cookie, API key, or Authorization header) were actually sent with the request, and whether they've expired.
Fix
Re-authenticate (log in again, refresh the token/API key) and ensure the credential is attached to subsequent requests.
Verify
Retry the request with valid, current credentials and confirm it succeeds.