AVAssetDownloadDelegate methods for HLS caching not getting called

I was running the code on simulator and

Downloading HLS streams is not supported on simulator.

I figured it out when I used the delegate method mentioned below.

- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(NSError *)error {

}

And now struggling for the whole day, I found a sample by Apple here and got the real reason behind the problem.