48 CFR §32.602

1. (a)The contracting officer has primary responsibility for identifying and demanding payment of contract debts except those resulting from errors made by the payment office. The contracting officer shall not collect contract debts or otherwise agree to liquidate contract debts (e.g., offset the amount of the debt against existing unpaid bills due the contractor, or allow contractors to retain contract debts to cover amounts that may become payable in future periods).
2. (b)The payment office has primary responsibility for—
   1. (1)Collecting contract debts identified by contracting officers;
   2. (2)Identifying and collecting duplicate and erroneous payments; and
   3. (3)Authorizing the liquidation of contract debts in accordance with agency procedures.