There are two ways to disapprove an affiliate:
On your Affiliates Overview, check the box next to the affiliate you'd like to disapprove. The option to disapprove from all program will appear near the top.
If your affiliate is a part of multiple programs and you'd only like to disapprove them from one, click on the affiliate and open the details panel. Here you can see the programs the affiliate is a part of as well as their status within those programs.
To change an affiliate's status, click on "Approved." This opens a drop down menu that includes the option to disapprove the affiliate.
Note: Please note that disapproving an affiliate from a program is not the same as deleting the affiliate. When you disapprove an affiliate, their information is archived. When you delete an affiliate, their data is permanently deleted.