Affiliate accounts can be deleted. Go to the affiliate list, turn on the compact view and then all you have to do is click on an affiliate from the affiliate list, and you will be able to delete them.
Then you select the affiliate you wish to delete, and you click the Delete button.
It will then ask you if you are sure you want to delete this affiliate.
Deleting an affiliate does not delete your historical data. The affiliate is anonymized and shown as a DELETED_... user instead of their details.
If you would like to disable an affiliate's account, look for the Account status field and choose the option Disabled. Once you do so, the affiliate won't be able to log in to your affiliate program again unless you activate their account.
You can also decide if you only block the affiliate's access to the platform (Account status) or if you choose to block also their traffic (Traffic status). These are two independent options. If you wish to block all the clicks so you don't pay commissions for that affiliate's traffic, you have to also block their traffic by changing the Traffic status field to Disabled.
