UiPath.MachineLearningExtractor.Activities.Exceptions.MLRequestException: Invalid server

I am trying to execute “DataExtraction - ML Extractor - Demo” in the Studio and experincing below error …I have looked at other Topics related to this but it seems its about brining up server …

Error:

19.12.0-beta.61+Branch.release-v2019.12.0.Sha.c5ef64a84dd6be2c140a75da8fd036824faab942

Source: Machine learning extractor

Message: Invalid server response.

Exception Type: UiPath.MachineLearningExtractor.Activities.Exceptions.MLRequestException

RemoteException wrapping UiPath.MachineLearningExtractor.Activities.Exceptions.MLRequestException: Invalid server response. —> RemoteException wrapping System.Net.Http.HttpRequestException: Response status code does not indicate success: 400 (BAD REQUEST).
at System.Net.Http.HttpResponseMessage.EnsureSuccessStatusCode()
at UiPath.MachineLearningExtractor.Activities.Services.MLRequester.d__4`1.MoveNext()
— End of inner exception stack trace —
at UiPath.MachineLearningExtractor.Activities.DataExtraction.MachineLearningExtractor.EndExecute(AsyncCodeActivityContext context, IAsyncResult result)
at System.Activities.AsyncCodeActivity.System.Activities.IAsyncCodeActivity.FinishExecution(AsyncCodeActivityContext context, IAsyncResult result)
at System.Activities.AsyncCodeActivity.CompleteAsyncCodeActivityData.CompleteAsyncCodeActivityWorkItem.Execute(ActivityExecutor executor, BookmarkManager bookmarkManager)

end point:

https://invoices.uipath.com

this end point is not working…any help on tis appreciated?