OData Feed error for entity lists AdxPortal online 8.1

 OData Feed error for entity lists is not retrieving any data for Adx portal online 8.1
My odata feed : msddemoportal.microsoftcrmportals.com/.../lead
All the necessary settings have been enabled (enabled OData in CRM at Portals->Entity Lists->LeadManagement )

I have enabled view and also provided Entity type and Entity Set Name. But while trying the odata feed url I am getting the below error.

{
  "odata.error":{
    "code":"","message":{
      "lang":"en-US","value":"An error has occurred."
    }
  }
}

Any thought would be appreciated.

-Arun