Automatic Subtask creation does not email Assignee

[Steven Lloyd]

Using JIRA Cloud I have looked to set up a workflow which creates sub-tasks dependant on values within a user picker custom field after a transition. The user of the custom field is then automatically assigned to said sub-task to complete work. However the User/Assignee of the sub-task does not receive an email to say they have been assigned a task or anything has been set up. 

Current Assignee is set up within the notification scheme on Issue created and Issue Assigned yet there does not seem to be anything received. Although emails are sent when Standard issue types are assigned out manually, which suggests that this is not an issue with the email settings rather with something I have forgot to do. 

Is anyone aware of this being an issue, or have an idea where I am potentially going wrong.

Cheers