If the payment is overdue, it will not only result in a 5% late payment fee (minimum 10 yuan) for the lowest unpaid part, but also a full penalty interest (five ten thousandths of the daily interest, which will be calculated from the day of consumption and compounded monthly until the principal and interest are paid off), and it will also produce a bad credit record in the Credit Information Center of the People's Bank of China.

Late payment fee for this period = 30000/ 10 * 5% = 150.

Penalty interest = 30,000 * 0.05% * (days between consumption date and repayment date)