Start by opening a project in Jira and select the issue you want to track time on. Open the issue and you’ll see the time-tracking widget.

Next, select the budget you are working on. The name of the budget will appear along with the logo of the client. Under the name, you’ll see a list of services you can track time against. Select the service you are working on, and add a description (optional).

If you want to start the timer, just scroll down and hit Start. For manual time entries, add the desired time entry and click Save.

Have in mind that edits of time entries have to be done in Jira Worklog to be visible in Productive. On the other hand, if you edit a time entry in Productive, the change will not be reflected in Jira Worklog. 

Productive will store the following information about the Jira issue where the time entry was recorded:

This information can be used in Productive's time entry insights as fields and filters:

Keep in mind that this information is synced only once - when the time entry has been recorded.
Any issue modifications in Jira will not be reflected in Productive.