I added a notification configuration to the Amazon S3 Bucket.
(Set Notification to AWS SQS when an object is created in a specific bucket.)
And, when BPA task connects to SQS and receives message and decodes it, 

error occurs.

In general, an example of an Amazon Notification message is:

--------------------------------------------------------

{
  "Records": [
    {
      "eventVersion": "2.0",
      "eventSource": "aws:s3",
      "awsRegion": "ap-northeast-2",
      "eventTime": "2017-04-18T06:07:57.321Z",
      "eventName": "ObjectCreated:Put",
      "userIdentity": {
        "principalId": "AWS:AIDAJEQBDECHCBKSOHD32"
      },
      "requestParameters": {
        "sourceIPAddress": "xxx.xxx.xxx.xxx"
      },
      "responseElements": {
        "x-amz-request-id": "6F2D9717DEA880BC",
        "x-amz-id-2": "W+hxP3PShHj2JjAco8ZqgWZFu+Hs8CZKcT0v3CIgZXpMbpx2obu7pElusICqMLpN8T8YEljeJvk="
      },
      "s3": {
        "s3SchemaVersion": "1.0",
        "configurationId": "demo.sqsEvent",
        "bucket": {
          "name": "demobucket",
          "ownerIdentity": {
            "principalId": "A61YNLACFCRNT"
          },
          "arn": "arn:aws:s3:::Demo.xxxxxxxx"
        },
        "object": {
          "key": "get_download+%288%29.zip",
          "size": 201966,
          "eTag": "0fa7a54a53d4e165792e2b01f77819e2",
          "sequencer": "0058F5AD3D49885BB5"
        }
      }
    }
  ]
}

--------------------------------------------------------

if there is no "x-amz-request-id" and "x-amz-id-2" in the list of keys

 in the above Json message, there is no error

It would be very inconvenient if the key string does not contain dash character.