The amount due specified in any bill from the department shall be conclusive on the organization unless, not later than fifteen days after the bill was mailed to its last known address or otherwise delivered to it, the organization files an application for redetermination or an appeal to the department, setting forth the grounds for such application or appeal. The department shall promptly review and reconsider the amount due specified in the bill and shall thereafter issue a redetermination in any case in which such application for redetermination has been filed.
SDCL 61-5A-30