Unable to sync ODK aggregate with GoogleSheets

1. What is the problem? Be very detailed.

I want to publish the ODK Aggregate submissions data into GoogleSheets

I have set up an OAuth2 Service Account following the steps outlines in the document and all went through without any error being reported.

I have then gone to Submissions tab and published the form to Google Spreadsheet selecting BOTH Upload Existing & Stream New Submissions Data giving the workbook name and my email. This works successfully.

I then get a mail in my gmail inbox sating - Transfer of ownership.

The spreadsheet only has the column headers and nothing else.

I try to Form Management --> Published Data tab and it is in ACTIVE_PAUSE.

2. What app or server are you using and on what device and operating system? Include version numbers.

I am using ODK Aggregate v2.0.2

3. What you have you tried to fix the problem?

Here is the tomcat logs from the ODK Aggregate: the ubiquitious NullPointerException!

Pasted below.
Anyone seen this?

4. What steps can we take to reproduce the problem?

5. Anything else we should know or have? If you have a test form or screenshots or logs, attach below.

====================catalina.out==============

Apr 25, 2019 1:27:55 PM org.opendatakit.aggregate.task.UploadSubmissionsWorkerImpl sendSubmissions
SEVERE: Error
org.opendatakit.aggregate.exception.ODKExternalServiceException: java.lang.NullPointerException
at org.opendatakit.aggregate.externalservice.GoogleSpreadsheet.insertData(GoogleSpreadsheet.java:597)
at org.opendatakit.aggregate.externalservice.AbstractExternalService.sendSubmission(AbstractExternalService.java:148)
at org.opendatakit.aggregate.task.UploadSubmissionsWorkerImpl.sendSubmissions(UploadSubmissionsWorkerImpl.java:277)
at org.opendatakit.aggregate.task.UploadSubmissionsWorkerImpl.uploadSubmissions(UploadSubmissionsWorkerImpl.java:239)
at org.opendatakit.aggregate.task.UploadSubmissionsWorkerImpl.uploadAllSubmissions(UploadSubmissionsWorkerImpl.java:162)
at org.opendatakit.aggregate.task.UploadSubmissions.lambda$createFormUploadTask$0(UploadSubmissions.java:35)
at org.springframework.scheduling.support.DelegatingErrorHandlingRunnable.run(DelegatingErrorHandlingRunnable.java:54)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.NullPointerException
at org.opendatakit.aggregate.externalservice.GoogleSpreadsheet.createAppendCellsRequest(GoogleSpreadsheet.java:622)
at org.opendatakit.aggregate.externalservice.GoogleSpreadsheet.insertData(GoogleSpreadsheet.java:560)
... 13 more