delete an existing set time (in hours) that is set as estimation from jira issue

[Narbeh Yousefian]

There are legacy issues that contain time tracking estimation. How do you delete these from Tasks that have had time logged against the ticket. 

Example, Estimation (in hours) is 8 hours for an issue type Task. This Task has 2 hours logged against it. How do I remove the estimation of 8 hours, leaving behind only the 2 hours logged?

[Andy Heinzer]

You are not expected to be able to update the Original estimate of an issue that already has some time logged against it.  However you can adjust the Remaining estimate anytime that you log work against the issue.   You can follow the steps in Logging work on issues: Setting a time estimate for an issue to see how this can be done.

If you are more concerned with being able to change the original estimate value despite this design aspect of Jira, then I would recommend checking out this related thread for a more in-depth explanation of this as well as other possible ways around this:  https://community.atlassian.com/t5/Jira-questions/How-can-I-update-Original-Estimate-after-work-has-been-logged/qaq-p/120560

[Narbeh Yousefian]

Thanks for the reply Andrew. I managed to sort it out by creating new issues and applying logged time only to these. I have another issue which was resolved by a community member recently which will add context as to why I want to modify or delete original estimates on Task Issues. 

https://community.atlassian.com/t5/Jira-questions/Remove-time-tracking-original-estimation-field-from-all-issue/qaq-p/715865