You can do this at any time by logging into the online portal at zable.com/loans/login
If you pay more than the amount that is due, the extra amount goes toward your loan balance. If your loan is current, an extra amount is applied to both the interest and principal on the loan. As a result you can expect fewer scheduled payments, a smaller final payment, or both. Paying more than is due will also save you on interest on the loan overall.
If you have any issues or questions, please contact us at customer@support.zable.com.