Were I you, I'd contact my bk lawyer and see if he'd hande this on a contingency.
If not, respond to the summons with a copy of your bk discharge and and the creditors matrix showing this creditor has been listed. Also, get a pacer account and see if you're still in the system.
PACER Service Center Home Page
One of the last entries will be a listing of creditors notified by the bk court clerk of your discharge as well as the method used . Either electronically or by mail. Include this in your responce as well.
I'd also inlude this from the bk code dealing with discharge.
(a) A discharge in a case under this title--
(1) voids any judgment at any time obtained, to the extent that such judgment is a determination of the personal liability of the debtor with respect to any debt discharged under section 727, 944, 1141, 1228, or 1328 of this title, whether or not discharge of such debt is waived;
(2) operates as an injunction against the commencement or continuation of an action, the employment of process, or an act, to collect, recover or offset any such debt as a personal liability of the debtor, whether or not discharge of such debt is waived; and
(3) operates as an injunction against the commencement or continuation of an action, the employment of process, or an act, to collect or recover from, or offset against, property of the debtor of the kind specified in section 541(a)(2) of this title that is acquired after the commencement of the case, on account of any allowable community claim, except a community claim that is excepted from discharge under section 523, 1228(a)(1), or 1328(a)(1), or that would be so excepted, determined in accordance with the provisions of sections 523(c) and 523(d) of this title, in a case concerning the debtor's spouse commenced on the date of the filing of the petition in the case concerning the debtor, whether or not discharge of the debt based on such community claim is waived.
11 U.S.C. 524
Of course, all this assumes the debt was the sort eligible for discharge.
