Since we are clearing the value of a custom field called Reason for Freezing, we need to have a Text field (multi-line) custom field created and add it to the screens used by the project.

By default, Jira comes with a post function that can change the values for standard issue fields, but since Reason for Freezing will be a custom field, we need to have the JSU Automation Suite for Jira Workflows app installed.

You can download it from the following link, or install it directly using the UPM: https://marketplace.atlassian.com/plugins/com.googlecode.jira-suite-utilities.