Miss. Code Ann. § 71-5-383

The commission is authorized and empowered to refund, without interest, such contributions, interest, and penalties as it may determine were paid erroneously by an employer, or may make or authorize an adjustment thereof in connection with subsequent contribution payments, provided the employer shall make written application for such refund or adjustment within three (3) years to the last day of the calendar year in which the services of individuals in employment, with respect to which such contributions were erroneously paid, were performed. For like cause and within the same period, adjustment or refund may be made on the commission's own initiative.