Jira Hosted only:The Reports and Timesheets for Jira and Timesheets for Jira app require an Application link to be set up between the app and Jira Software.
...
Appfire API:
Navigate to My Area > Appfire API. For more information, refer to Appfire API.
Report subscriptions:
Navigate to My Area > My Saved Reports.
To subscribe to any of the reports, under the Subscription column, click Email this report. For more information, refer to schedule reports for automated delivery (subscriptions)
Setup the Application link in Jira hosted
...