(A) Upon receipt of a notice pursuant to section 3119.87 of the Revised Code, the child support enforcement agency administering a child support order, within twenty days after receipt of the notice, shall complete an investigation. The agency administering a child support order may conduct an investigation upon its own initiative if it otherwise has reason to believe that there may be a reason for which the order should terminate. The agency's investigation shall determine the following:

1. (1) Whether any reason exists for which the order should terminate;
2. (2) Whether there are other children subject to the order;
3. (3) Whether the obligor owes any arrearages under the order;
4. (4) Whether the agency believes it is necessary to continue withholding or deduction pursuant to a notice or order described in section 3121.03 of the Revised Code for the other children or arrearages;
5. (5) Whether child support amounts paid pursuant to the order being investigated should be impounded because continuation of receipt and disbursement would lead to an overpayment by the obligor.