Poll an export job by job ID. accepted and processing are nonterminal states; finished and failed are terminal. Result URLs are omitted until the job is finished, and failed jobs do not produce result files; inspect message for details.

A finished campaign or creative job returns resultsUrls; other finished jobs return resultsUrl. Result URLs expire 24 hours after generation, so download files promptly. A finished job may omit result URLs after its files are no longer available. If message is File does not exists anymore, submit a new export job to recreate the files.