2. Service upon an obligor's payor or successor payor under this section shall be made by prepaid certified mail, return receipt requested, or in the manner prescribed in chapter 48.
(c)1. The obligor, within 15 days after service of a notice of delinquency, may apply for a hearing to contest the enforcement of the income deduction on the ground of mistake of fact regarding the amount owed pursuant to an order establishing, enforcing, or modifying an obligation for alimony, for child support, or for alimony and child support, the amount of the arrearage, or the identity of the obligor, the payor, or the obligee. The obligor shall send a copy of the pleading to the obligee and, if the obligee is receiving IV-D services, to the IV-D agency. The timely filing of the pleading shall stay service of an income deduction order or, in Title IV-D cases, income deduction notice on all payors of the obligor until a hearing is held and a determination is made as to whether enforcement of the income deduction order is proper. The payment of a delinquent obligation by an obligor upon entry of an income deduction order shall not preclude service of the income deduction order or, in Title IV-D cases, an income deduction notice on the obligor's payor.