Filestack uploadconfig parameters are ineffective

Question

Am using Filestack JS for uploader in my website. My code is as follows

var options = {
        uploadConfig: {
            retry: 5,
            progressInterval: 1,
            timeout: 60000,
            onProgress: (e) => {
                console.log('am progressing');
                console.log(e.totalPercent);
            }
        }
    };
filestack.picker(options).open();

Reference 1: https://filestack.github.io/filestack-js/interfaces/uploadoptions.html#onprogress

Reference 2: https://www.filestack.com/docs/uploads/pickers/web/#upload-options

The filestack onProgress event is not triggered at all. The file is just getting uploaded silent. How to get this event triggered when the file upload is being done by the picker ?