This is typically the result of the user rights not having the ability to send a final email message

In order to send a final message, work with a Supervisor user to upgrade your email access to send final. The task group associated with your role can be updated via:

Confirm the task group associated with the user:
  1. Navigate to Users & Security>Users
  2. Click the Pencil icon next to the user in question
  3. Note their associated role under Role
  4. Navigate to Users & Security>Roles
  5. Click the pencil icon next to the Role noted above
  6. Click the Security Assignment tab
  7. Note the Task Group listed
Edit the rights of the task group to include the ability to send final email messages:
  1. Navigate to Users & Security>Task Groups
  2. Click the pencil icon next to the task group in question
  3. Locate and expand Email security, if it is not expanded
  4. Expand Email Tasks, if it is not expand
  5. Mark the box for Send rights
  6. Click Save