To edit the custom fields in the reporting, go to 'Data Insights' and 'Calls'
Click on the 'Fields' button
Scroll to the bottom and click "Edit Custom & Revenue"
Scroll to the column of the report labeled "Edit Custom & Revenue" and click "Edit Fields"
Enter a custom value or click in the text area to access the preselected drop-down fields:
Click on 'Submit' to save the values