Doubleclick Search API Explorer: 'Login Required' for reports.GetFile - login-required

Question

Quick question re: a 401 error I'm running into when executing a report.getfile in the Doubleclick Search API Explorer (full error message below) .
I am currently logged into my google account that is used for Doubleclick Search. I've tried logging in on a different browser, as well.
I've gone through the 'report.request' and 'report.get' executions without issue. I only get this error when I get to this point. "isReportReady" is also true before I execute 'report.getfile'. Full list of requests/responses below this initial message.
My understanding is that with API Explorer, I should just be able to turn on the OAUTH2.0 and execute, but correct me if I'm wrong!
"domain": "global",
"reason": "required",
"message": "Login Required",
"locationType": "header",
"location": "Authorization"
"code": 401,
"message": "Login Required"
If any additional details are needed definitely let me know. The only questions I've seen come up in here seem to be more-so based around manual coding, or other API Explorer services.
Thanks in advance for any insight!
reports.Request (Response)
POST https://www.googleapis.com/doubleclicksearch/v2/reports?fields=isReportReady%2Crequest%2Fcolumns%2FcolumnName&key={YOUR_API_KEY}
{
"downloadFormat": "csv",
"maxRowsPerFile": 6000000,
"reportType": "conversion",
"statisticsCurrency": "agency",
"reportScope": {
"agencyId": "xxxxxxxxxxxxxxxxxxxx",
"advertiserId": "xxxxxxxxxxxxxxxxxxx"
},
"timeRange": {
"startDate": "2014-01-1",
"endDate": "2016-11-3"
},
"columns": [
{
"columnName": "conversionVisitExternalClickId"
},
{
"columnName": "conversionTimestamp"
},
{
"columnName": "keywordid"
},
{
"columnName": "adGroup"
},
{
"columnName": "campaign"
},
{
"columnName": "account"
},
{
"columnName": "floodlightActivity"
},
{
"columnName": "conversionID"
}
]
}
reports.Get (Response)
"kind": "doubleclicksearch#report",
"id": "xxxxxxxxxxxxx",
"isReportReady": true,
"request": {
"reportScope": {
"agencyId": "xxxxxxxxxxxxxxx",
"advertiserId": "xxxxxxxxxxxxx"
},
"reportType": "conversion",
"columns": [
{
"columnName": "conversionVisitExternalClickId"
},
{
"columnName": "conversionTimestamp"
},
{
"columnName": "keywordId"
},
{
"columnName": "adGroup"
},
{
"columnName": "campaign"
},
{
"columnName": "account"
},
{
"columnName": "floodlightActivity"
},
{
"columnName": "conversionId"
}
],
"timeRange": {
"startDate": "2014-01-1",
"endDate": "2016-11-3"
},
"includeRemovedEntities": false,
"downloadFormat": "csv",
"statisticsCurrency": "agency",
"maxRowsPerFile": 6000000
},
"statisticsCurrencyCode": "USD",
"statisticsTimeZone": "America/New_York",
"rowCount": 5225201,
"files": [
{
"url": "https://www.googleapis.com/doubleclicksearch/v2/reports/AAAncMCcKrSJ9MS_/files/0",
"byteCount": "1271002762"
}
]
}
reports.getFile (Response)
GET https://www.googleapis.com/doubleclicksearch/v2/reports/AAAncMCcKrSJ9MS_/files/0?key={YOUR_API_KEY}
200
- Hide headers -
cache-control: private, max-age=0, must-revalidate, no-transform
content-length: 1694670352
Content-Type: text/csv
date: Tue, 21 Mar 2017 14:24:03 GMT
etag: W/"u6ybyji1w_vhYZMTUlOUhEWemRI/nWLUgbdAKD9EU6srfscDcZyGxz8"
expires: Tue, 21 Mar 2017 14:24:03 GMT
server: UploadServer
vary: Origin, X-Origin
x-guploader-uploadid: AEnB2UoZzz4AafhGUKg-1edKZWLCmiML_a6HnP7lr11aD7tXZAnEIgyEno9ZhHOCbJ02XTlAkgtYcD4AOGbhmar6dpSx-uzh-n_6SCQH-iShQma-k6GLsMk