The article outlines the steps How to update an existing Rep Commission% and Discount%
FOLLOW STEPS BELOW:
1. Navigate to the relevant customer by clicking Administration-> Customers in the navigation pane.
2. Open the Sales Reps tab on this customer.
3. Double click on the line you would like to update and enter the Discount% and Commission% Values.
4. To bulk update multiple lines select the required lines.
5. Click adjust values and enter the new commission% and discount%.
NB. For a quick tutorial watch below