Repay the unamortized principal in advance by installments. According to the query of financial ladder network, it means that after the user repays in advance, the repayment amount is not included in the total repayment amount. The special installment of bank card and credit card means that when the cardholder uses the third-party payment software to repay the credit card arrears, the savings card is bound to the mobile banking for online consumption or cash withdrawal.