Students not receiving Samigo email notification

Before starting, make sure a student registers with his email.
1. Login as Instructor, Select one of course test site, Tests and Quizzes.
2. Enter an Assessment title -> Click on 'Create'
3. Create some questions and then Click on 'Publish'
4. In the 'Publish Assessment' page, Select 'and send notification to below students' and Click 'Publish'

Problem:
1. Student doesn't receive an email stating the assessment is published
2. The same problem arises while adding a student to a site and opting to send a notification

https://www.evernote.com/l/ATkJqXqIZ0ZO97NomZzepyW8Wnx7LTX2QIQ