RetrieveAvailableReports Samplecode is Running.. 
stdClass Object
(
    [response] => stdClass Object
        (
            [rmsg] => Authentication Failed
        )

)
[401] Error connecting to the API (https://api.cybersource.com/reporting/v3/reports?startTime=2019-09-01T00%3A00%3A00.0Z&endTime=2019-09-05T23%3A59%3A59.0Z&timeQueryType=executedTime)