(a) Upon final determination of the amount of the debt due and owing by means of the hearing provided by Code Section 48-7-165 or by the taxpayer's default through failure to comply with subsection (c) of Code Section 48-7-164, the claimant agency shall remove the amount of the debt due and owing from the escrow account established pursuant to Code Section 48-7-164 and shall credit the amount to the debtor's obligation.

(b) Upon transfer of the debt due and owing from the escrow account to the credit of the debtor's account, the claimant agency shall notify the debtor in writing of the finalization of the setoff. The notice shall include a final accounting of the refund which was set off, including the amount of the refund to which the debtor was entitled prior to setoff, the amount of the debt due and owing, the amount of the refund in excess of the debt which has been returned to the debtor by the department pursuant to subsection (b) of Code Section 48-7-164, and the amount of the funds transferred to the claimant agency pursuant to Code Section 48-7-164 in excess of the debt finally determined to be due and owing at a hearing held pursuant to Code Section 48-7-165, if such a hearing was held. At such time, the claimant agency shall refund to the debtor the amount of the claimed debt originally certified and transferred to it by the department in excess of the amount of debt finally found to be due and owing.