Any judgment creditor, upon having a garnishment summons issued upon a judgment against the judgment debtor named in such certificate, may give five days’ written notice, to be served personally on the employer and the judgment debtor by any officer authorized by law to serve civil process, that he will apply to the court or judge who issued such certificate to have the same revoked, and, upon proof that the holder of the certificate is no longer entitled to the exemption allowed thereby, the court or judge shall revoke the same and require the holder to deliver such certificate to the court, which shall cancel the same.