Task manager with email notification

Summary:

Hi, we are trying to create a basic tasks schedule using the Task manager.

Something like this

Tax Data preparation- Parent Task

Send 1st reminder - Basic task. Start Date set to Day-14

Send 2nd reminder - Basic task. Start Date set to Day- 7

Enter tax data - Data form task

Review and submit tax data - Data form task

However, we are not able to send an email notification. we have set the email notification option from the Manage System Settings. still not working

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