User Name Is Not Displayed as Created by/Updated by Information in History
If user name is not displayed as the Created by/Updated by information in History, you might not have view permission for "Created by" or "Updated by" field.
Change the permission settings for "Created by" or "Updated by" field by following the steps described below.
Only app administrators can change the settings.
Click the app setting button on the upper right of the record view.
Click "App Settings" tab, and then select Fields under "Permissions".
In the "Target Field" column, check the current setting for "Created by" or the "Updated by" field, and then select the "View" for the user to whom you want to give view permission for history.
You can also add individual user, department, or group first and then select "View", if necessary.
Click Save on the upper left side of the screen, and update the app.