The "Grade history" report in the gradebook has been disabled to ensure there are no slowdowns on Moodle.

The report is used by instructors to see the history of changes made to a grade item.

If you are an instructor and you need to see this information, please submit a ticket to the IT Support Centre. Please include the NetID of the student and the grade item you need the data for. The Moodle team will get the data for you.