La. Stat. tit. 23 § 1551
If not later than three years after the due date for payment of contributions, an employing unit which made payment of any amount of contributions, interest or penalties shall make application for an adjustment thereof in connection with subsequent contribution payments, or for a refund thereof because such adjustment cannot be made, and the administrator shall determine that such contributions or interest or penalties or any portion thereof were erroneously collected, the administrator shall allow such employing unit to make an adjustment thereof, without paying interest upon the same, in connection with subsequent contribution payments by it, or if such adjustment cannot be made the administrator shall refund said amount, without interest upon same from the unemployment compensation fund. For like cause and within the said period, adjustment or refund may be so made on the administrator's own initiative.
If not later than three years from the date on which an administrative error is committed, the error is discovered and called to the attention of the administrator, he shall, on his own motion or upon the request of any interested party, take all necessary steps that he may deem necessary to correct and rectify the said error; provided, however, that any interest, fine or penalty refunded under this section which has been paid into the special unemployment security administration fund established pursuant to R.S. 23:1513 shall be paid out of such fund. However, the administrator has no authority to make any adjustment or correction which will increase the contribution of any employing unit unless such adjustment or correction is made within twelve months of the occurrence of the administrative error.
La. R.S. § 23:1551