Google fit api returning empty bucket while fetching last week data

Question

I am trying to fetch step count data of last week or last 7 days. I am getting the empty list of bucket which holds the data.

//Check how many steps were walked and recorded in the last 7 days
        DataReadRequest readRequest = new DataReadRequest.Builder()
                .aggregate(DataType.TYPE_STEP_COUNT_DELTA, DataType.AGGREGATE_STEP_COUNT_DELTA)
                .bucketByTime(1, TimeUnit.DAYS)
                .setTimeRange(startTime, endTime, TimeUnit.MILLISECONDS)
                .build();

        DataReadResult dataReadResult = Fitness.HistoryApi.readData(mGoogleApiClient, readRequest).await(1, TimeUnit.MINUTES);