CA Fin Code Section 22751

(a)

If any amount other than or in excess of the charges permitted by this division is charged or contracted for, or received, for any reason other than a willful act of the licensee, the licensee shall forfeit all interest and charges on the loan and may collect or receive only the principal amount of the loan.

(b)

Subdivision (a) shall not apply to an error in computation if (1) the licensee shows by a preponderance of evidence that the violation was not intentional and resulted from a bona fide error notwithstanding the maintenance of procedures reasonably adapted to avoid any such error, and (2) within 60 days of discovering the error the licensee notifies the borrower of the error and makes whatever adjustments in the account are necessary to correct the error.