We are sorry to hear about this issue with multiple plans but only one order. Please immediately contact the Merchant where you made your purchase to explain the situation. We need the Merchant to give us approval to cancel the extra installment plan, and once they do, we will resolve this for you right away.
We definitely want to assist you, but even in this case we cannot make changes to an installment plan without approval from the Merchant. If you include support@splitit.com on your email to them, we can stay in the loop and provide information as needed to help your case.