(a) Except as provided in subsection (b) of this section an employer upon whom levy is served, and who—
(1) at the time is indebted for wages to an employee who is the judgment debtor named in the levy, or
(2) becomes so indebted to the judgment debtor in the future, shall, while the levy remains a lien upon such indebtedness, withhold and pay the judgment creditor or his legal representative, within fifteen days after the close of the last pay period of the judgment debtor ending in each calendar month, that percentage of the gross wages payable to the judgment debtor for the pay periods in such calendar month to which the judgment creditor is entitled under any levy until such levy is wholly satisfied.
(b) Upon written notice of any court proceeding attacking the levy or the judgment on which it is based the employer shall make no further payments to the judgment creditor or his legal representative until receipt of an order of court terminating the proceedings.
(c) Any payments made by an employer-garnishee in conformity with this chapter shall be a discharge of the liability of the employer to the judgment debtor to the extent of the payment.