People who want free advice are welcome to post here. So are people who want to point out, for the benefit of all readers, how it is important to know as many facts as possible, before suggesting a solution.

After my first reading, I thought you were saying that the client denied receiving the CP-2000 in October 2023. Every CP-2000 I have seen tells the taxpayer not to file an amended return, just respond to the notice. They also list the sources of 1099 information matched to the return. So was anything done with the CP-2000? Or did your involvement just start after the March 2024 SNOD?

We now learn that you are using TurboTax to file amended returns. For the benefit of others here, that is not the way to respond to a CP-2000 or a SNOD.

The “Merchant Category Code” here of 8661 is a clue. That is for Religious Organizations. There is a person with a name that fits your client’s abbreviated version, who lives in Maryland, where based on earlier posts you seem to have some connection. He is involved with a religious organization, which has an address that starts with 301 KE. So what I see here, just wildly speculating, is maybe this money was paid to the church, and at some point someone asked for a name and SSN, and your client made the mistake of giving them his. Maybe these are donations? From Intuit employees? Intuit sells software, I don’t know why they would be issuing a 1099-K to a religious organization, maybe Intuit expert @Jim-from-Ohio knows.

At this point, stop the train from leaving the station by filing the Tax Court petition, making sure to US mail it to the right address and not to use one of the FedEx or UPS methods that is not acceptable. Keep proof of mailing. Don’t wait until the last minute. The case will be assigned to an Appeals officer in due course –  maybe six months – and you can work it out then. Tell your client that the road to Hades is paved with good intentions, but if someone asks for his SSN, keep his mouth shut and his pen in his pocket.