aws-lambda-dotnet: await Task does not work as expected

Hello AWS,

I am working with async calls using in lambda handler. However, the program does not work as expected. Error: "errorMessage": "RequestId: 991fc1fc-1558-11e7-bd03-3bb3c9d9b1b0 Process exited before completing request"

So I did some logging, it seems that the program ran the first line of code, but stopped when running the second one. Is there anything wrong with the way I am writing the async call?

Thanks!

public async Task FunctionHandler()
{
    var sqsClient = new AmazonSQSClient();
    var sqsResponse = await sqsClient.ReceiveMessageAsync(QueueUrl);

    foreach (var message in sqsResponse.Messages)
    {
              // do something
    }
}