Your right about that challenge jurisdiction by all means. You also need to know a few other things.
“Anyone entering into an arrangement with the government takes the risk of having accurately ascertained that he who purports to act for the government stays within the bounds of his authority, even though the agent himself may be unaware of the limitations upon his authority.” Federal Crop Insurance v. Merrill, 332 U.S. 380 (1947). You have to correct the erroneously allegations against you about your earnings.
They are not taxable but you fail to rebut that.
“In the interpretation of statutes levying taxes it is the established rule not to extend their provisions, by implication, beyond the clear import of the language used, or to enlarge their operations so as to embrace matters not specifically pointed out. In case of doubt they are construed most strongly against the government, and in favor of the citizen.” (cites omitted) Gould v. Gould, 245 US 151 (1971).
“Keep in mind the well settled rule that the citizen is exempt from taxation unless the same is imposed in clear and unequivocal language, and that where the construction of a
law is doubtful, the doubt is to be resolved in favor of those upon whom the tax is sought to be laid.” Spreckles Sugar Refining Co. v. McClain, 192 US 397 (1904).
The federal law is mathematically consistent that only “wages” as defined at IRC §3401(a) and §3121(a) are returnable as earnings from labor under federal law. There is no doubt that unprivileged pay-for-labor not constituting “wages,” as custom defined in the code, is exempt from reporting.
“Where a state official receives money for a tax paid under duress with notice of its illegality, he has no right to it and the name of the state does not protect him from suit.” Atchison, T. & S. F. R. Co. v. O'Connor, 223 U.S. 280
“The taxpayer must be liable for the tax. Tax liability is a condition precedent to the demand. Merely demanding payment, even repeatedly, does not cause liability.” Bothke v. Terry, 713 F.2d 1405, 1414 (1983).
“…if doubt exists as to the construction of a taxing statute, the doubt should be resolved in favor of the taxpayer...” Hassett v. Welch., 303 US 303, 314, (1938)
Speaking of “doubt,” you would have to agree, would you not, that (1) not all earnings qualify as “income” subject to reporting, that (2) it is possible for “information returns” to be wrong, and (3) the written specifications of the law provide that only receipts qualifying as “wages,” as defined at IRC §3401(a) and §3121(a), or payments made in connection with a “trade or business” are to be listed on relevant “information returns?” Because these terms are defined in the code, I am constrained by the rules of statutory construction that the commonly held definition does not apply
 “Words of art” have the specific definition given to them in IRC. Words defined in the codes using the term “include” cannot be presumed to have their ordinary meaning plus the special definition given, rather the custom definition exclusively,