All API requests are signed using your Cloudinary's API Key and Secret. For better security, the signature is valid for one hour. Therefore, all API calls and the signatures include the 'timestamp' parameter that should be set to the current time (Unix time in GMT). Getting the "Stale request" error usually means that either your computer's clock is in the past or the timestamp was not calculated in GMT.
It is recommended to use our server-side SDKs, as those automatically add the signatures to all admin API, and upload API requests.