http://autarchic.tripod.com/dixon/chapter4.html
The next presentment may be a request for confirmation of your "protest" or ANY OTHER subterfuge indicating agency does not understand your demand.
The presentment may be from a different collection agency that has bought the supposed debt. The more third party intervention the better, because the weakness becomes more apparent and much harder to prove, because "the chain of evidence" is broken.
The collectors are hoping you fold and start payment or refuse as a means of forcing you to dishonor so they can win by default. If the same agency persist, return the instrument with a copy of the below stated "without dishonor" statement and a UCC 3-505.
Answer every presumed debt as if you know what you are doing. If you do not owe money or wise agency to "verify," the first presentment may be answered;
"I hereby refute the validity of your unattested presentment/claim, without dishonor, I do not owe this money." Sign, date, and write "without prejudice" UCC 1-207 on the face of the presentment demand, above your signature. Affix a certified post number to the "prima facie," which now becomes an evidence document for the trier of fact, and proves you are "express" in attempting to work out verification of the agency demand.
Mail the demand to the agent via return receipt requested.
The individual agent is on "notice" that you are not waiving any rights and you want the instrument verified.
The agent will then need to swear an oath that the presentment is a legitimate "true bill," or find another fool who will commit perjury to do so.
The Common Law does not sue out the entire state or agency, it becomes more personal and the agent must use great caution.