You can't edit a submitted assignment, but you may be allowed to resubmit it. However, you can't resubmit all assignments. Check if you can submit an assignment more than once. If you can't and made a mistake, you must contact your instructor to ask for the opportunity to resubmit the assignment.
Hover over the cell and click on the contextual menu on the right side of the cell. Then select the View Grade Details from the drop-down menu. On the following page, click on the Clear Attempt button or Allow Additional Attempt. Clearing the attempt will completely remove the student's first attempt.
Note: Clearing a student's attempt will delete the student's attempt permanently. If you wish to keep a record of the student's attempt, but you want to allow the student to retake the exam, please refer to the instructions on ignoring a student's test attempt.Mar 4, 2019