Summons

Hello everyone! I received a summons a couple of days ago from CIR Law Offices for a debt acquired by Equable Ascent Financial. The summons says the Plaintiff, Equable Ascent Financial, alleges that I

"within the last four years, became indebted to "Plaintiff's Predecessor on an account assigned, transferred and/or sold to Plaintiff. Plaintiff's Predecessor will also be referred to as Plaintiff."

The name of the original creditor is nowhere stated in the summons, and no other information is stated as to when, who, and how I became indebted to this company. The only information is what I disclosed above. So how do I even know I owe this company?

What is the best way to answer this summons?

Thanks!