HTTP 404
course_not_foundCourse not found
No active course matches the supplied Udemy course ID or slug.
Resolution
Check the identifier or search the course catalog first.
Response handling
Keep the response's request_id for diagnostics. Retry only transient 429 and 503 responses, using the rate-limit headers and exponential backoff with jitter. Correct 400, 401, and 403 requests before retrying.