(1) If, after a return has been filed, the department finds that the tax paid with the return is more than the correct amount, it shall credit or refund the overpayment as is appropriate.
(2) In the case of any overpayment, the department may within the applicable period of limitations credit the amount of such overpayment, including any interest allowed thereon, against any part of the liability in respect of the tax giving rise to the overpayment of the taxpayer who made the overpayment, refunding any balance to such taxpayer.