Unable to get change of assignee name in history of an issue

[Basudev Behera]

We have write a code for automatic assignee in a project. Assignee is changed but it is not coming under History of an issue. So difficult to track it.

Please find the below code-

else if (event.getEventTypeId() == 9){

MutableIssue issue = event.getIssue();

//setting assignee to null
issue.setAssigneeId(null);

//setting QA Contact to null
CustomField cfQAContact = cfm.getCustomFieldObjectByName("QA Contact");
def currentQAContact = issue.getCustomFieldValue(cfQAContact);
updateCustomField(issue, cfQAContact, null, true);

issue.store();

//setting Additional Owners to null
CustomField cfAdditionalOwner = cfm.getCustomFieldObjectByName("Additional Owners");
ownerFlag =1;

Issue issue1 = event.getIssue();
IssueOnCreate(issue1);

issue1.store();

boolean wasIndexing = ImportUtils.isIndexIssues();
ImportUtils.setIndexIssues(true);
ComponentAccessor.getIssueIndexManager().reIndex(issue1);
ImportUtils.setIndexIssues(wasIndexing);

Is there any code which can help to update the History?

[Basudev Behera]

Can anyone help me here?