PayKickstart has a feature that is automatically enabled to help cut down on affiliate commission fraud.
By default, if a customer purchases a product using their own affiliate link (or the customer/affiliate IP address and/or email match) we automatically deny the commission. This helps protect vendors, not paying out commissions to people who try to earn credit for their own purchase.
However there may be use-cases where the vendor may want to disable this feature. To do that, simply go to your Campaign settings and under the “Affiliate Program” section, click Disable.