When a user tries to edit the Status of an issue under Lists > Support > Issues, the value in the Assigned To field would automatically change depending on the Issue Status selected.
However, some users are changing the Assigned To field first before changing the Issue Status. This is not the correct way to do it. When this happens, NetSuite reverts the original value of the Assigned To field.
This is because each Issue Status is associated with an issue role type. Employees using roles with this issue role type can be assigned to issues of the associated status. For more information on how issue statuses are set up, see the topic Issue Statuses or search for SuiteAnswers ID 11055.
Therefore, as a best practice, users must change the Issue Status field first and let the system change the Assigned To field.