If you fail to pay all or part of a monthly Instalment Repayment, that amount:
a. will be overdue
b. will not form part of the humm90WRAP or humm90WRAP Remaining Balance;
c. will form part of the Unpaid Balance; and
d. interest (calculated at the Card Purchase Rate) will apply to the overdue amount. It will be debited to your humm90 Account on that overdue amount from the time it becomes overdue in accordance with the Conditions of Use.