This is my letter that I sent in response to their earlier notice...

I cannot evaluate your claim, and I do not consent to it without proof of your delegated authority, evidence of the instrument, and law you claim attaches a liability to me. For me to properly respond you must provide the following preliminary information:
1) Identify each and every person embraced by the pronoun “We” in your Notice. This includes each government agent who actually prepared, made, approved, or, in any manner prepared, signed or subscribed the Notice, or any document supporting the Notice, whether with his own name, an identification number, a pseudonym, or on behalf of another.
For each person identified in response to paragraph 1) provide the following documents, or information properly certified:
2) A business mailing address sufficient for service of process, phone number, employee identification number, civil service grade, and official title as of the Notice date.
3) A constitutional oath of office.
4) A civil commission as agent or officer of the government.
5) An affidavit regarding consideration to secure the office.
6) A personal surety bond.
7) For those identified who have no personal bond, that of the nearest bonded supervisory officer.
8) Identification of the entity or person who would be responsible for payment of any claims against the bonds.
9) Documentation establishing delegated authority, including all intermediaries from the Secretary to the subject person.
10) The Statute at Large that imposes a “form 1040” tax on me.
11) The Statute at Large that permits you to file a “form 1040” or variant, in my name without my consent.
12) The implementing regulation for the statute imposing a “form 1040 tax” on me. Cite the volume and page of the Federal Register where the regulation is published.
13) State the subject, category, character, and class of the proposed “form 1040 tax”.
14) State the current valid OMB number for the proposed substitute for return and indicate its current expiration date.
15) Each document, instrument and law you claim attaches to me a duty to submit a “form 1040” to you.
16) Each document, instrument and law you claim attaches to me a liability for the purported tax.
17) Identify all witnesses with first hand, factual knowledge, who can testify to facts establishing where, when, and how I was made liable for the tax. If none are known, say so plainly.
Failure to provide the requested information, verifying your authority and the validity of your Notice within 30 days from the date of this NOTICE, and before any further actions are taken against me, will be an admission that you and all parties referenced as “We” are recklessly and intentionally disregarding provisions of internal revenue law and its regulations. Please be aware that the Courts have found that a failure to verify lawful authority may expose you to loss of the civil immunity enjoyed by public officers acting within the law.

Of course they never responded to these valid questions! They defaulted.