(a) If a refund is not timely made, the driver training provider shall pay interest on the amount of the refund. Interest begins to accrue on the first day after the expiration of the refund period and ends on the day preceding the date the refund is made.
(b) The department shall establish annually the rate of interest for a refund at a rate sufficient to provide a deterrent to the retention of student money.

(c) The department may except a driver training provider from the payment of interest if the provider makes a good-faith effort to refund tuition, fees, and other charges but is unable to locate the student to whom the refund is owed. On request of the department, the driver training provider shall document the effort to locate a student.