I also received a CP11 saying that I calculated my tax wrong and that I owe an additional $898, which is EXACTLY the amount calculated by TurboTax on the Recovery Rebate Credit Worksheet. Essentially, the IRS notice seems to be saying that I'm not entitled to that credit. I have reread that worksheet about a hundred times now, and as I see it, we (married filing jointly with and AGI below 150K) should be entitled to $2800, but back in March 2021, we received $1902. I am also unable to get through to the number provided in the letter. I also contacted TurboTax, but unlike in prior years, where someone was able to advise me on it, I am being told that I need to talk to the IRS or a CPA. Is that the same?
