(a) When a default judgment is rendered against a garnishee under Code Section 18-4-21, 18-4-22, or 18-4-43, the plaintiff shall serve the garnishee, as provided in Code Section 9-11-4, or, when the garnishment is filed in a magistrate court, the plaintiff may serve the garnishee by using the constable of the magistrate court in the manner set forth in Code Section 9-11-4, with a copy of such default judgment. On a motion filed not later than 90 days from the date the garnishee was served with such default judgment, the garnishee may, upon payment of all accrued costs of court, have such default judgment modified so that the amount of such default judgment shall be reduced to an amount equal to the greater of $50.00 or $50.00 plus 100 percent of the amount by which the garnishee was indebted to the defendant from the time of service of the summons of garnishment through and including the last day on which a timely garnishee answer could have been made for all money or other property belonging to the defendant which came into the garnishee's hands from the time of service of the summons through and including the last day on which a timely answer could have been made and less any exemption allowed the defendant.

(b) On the trial of a motion to modify a default judgment, the burden of proof shall be upon any plaintiff who objects to the timeliness of the motion to establish that such motion was not filed within the time provided for by this Code section.