Cal. Fish & Game Code § 8057

If the department determines that any fee or penalty has been paid more than once or has been erroneously or illegally collected or computed, the department shall set forth that fact in the records of the department. The excess amount collected or paid shall be credited on any amounts then due and payable from the person under this part, and the balance shall be refunded to the person, or his or her successors, administrators, or executors.