Cal. Civ. Code § 1812.532

In the event that a nurses’ registry collects from a nurse a fee or expenses for an assignment, and the nurse fails to obtain the assignment, or the nurse fails to be paid for the assignment, the nurses’ registry shall upon demand therefor, repay to the nurse the fee and expenses so collected. Unless repayment is made within 48 hours after demand, the nurses’ registry shall pay to the nurse an additional sum equal to the amount of the fee.