Annual interest: 4000*5/ 10000*365=730, plus compound interest of 800.
One-year overdue fine: 4000 * 5/100 *12 = 2400.
Average late payment fee 1200.
Compound interest of overdue fine:1200 * 5/10000 *182 =109.8.
One year repayment: 4000+2400+800+109.8 = 7309.8.
Besides, your card can't be used and your credit history is not good. You can't get credit cards and loans in the future.