Workflow do not changes status after document update

Hi All,

Please advise. I've created workflow with enabled option "Enable Content Approval" (Update the approval status after the workflow is completed (use this workflow to control content approval).). I'm expecting this scenario:

1) I create document

2) Run workflow for this document

3) Approve document

4) status of document will change to the Approved

5) I'll edit document and save it.

6) Status of document should be changed from Approved to another one.

But, after the editing of document, status is Approved still . I'm excpecting that it will be changed.

Is it bug? How to fix it?