我没有通过使用restpai获取当前步骤数据

Question

我在24/04/2019有一些步骤数据，但输出为空。为什么？错误在哪里？

Request Body
------------
{    
    "aggregateBy" : [{    
          "dataTypeName": "com.google.step_count.delta",
        "dataSourceId": "derived:com.google.step_count.delta:com.google.android.gms:estimated_steps"  

    }],    
    "bucketByTime": { "durationMillis": 86400000 },

    "startTimeMillis": 1556044200000,  
    "endTimeMillis":     1556130599059  
}   
Request URl
------------
https://www.googleapis.com/fitness/v1/users/me/dataset:aggregate

O/p:
{
    "bucket": [
        {
            "startTimeMillis": "1556044200000",
            "endTimeMillis": "1556130599059",
            "dataset": [
                {
                    "dataSourceId": "derived:com.google.step_count.delta:com.google.android.gms:aggregated",
                    "point": []
                }
            ]
        }
    ]
}