I think many people have this problem. It has to do with the final Pandemic recovery allotment. Sure, the IRS gives a list of possible errors but they do not specifically state which error I had. But this is not the real problem. In completing my return on TurboTax, my income, Social Security, the size of my family, etc is all available. A little TurboTax research on the requirements for receiving the Pandemic allotments in addition to having me state whether I received the funds or not, could have made it possible for me to complete my tax onus and go on with the rest of my life.
