When adding third party apps or having to update apps to work with new Oauth versions you may have to grant data access.
- Go to admin.google.com
- Click on Apps --> Marketplace Apps --> the new app/app to be updated
- Directly under the title of the app you should see the Data access status:
- Click on Data access. The section will slide open:
- Click on Grant data access:
- Your app is now active and ready to be used