View Gradebook History
Instructors can view a complete record* of every grade entered and changed by accessing the Gradebook History. The log can be filtered by student, grader, assignment, and date.
This can be useful for confirming a grade change, verifying a date of entry, or recovering an earlier grade.
See the Canvas Guide:
How do I view the history of all grading changes in the Gradebook?
* Grade history is available for the previous 365 days.