When I hired on during Covid in January 2021, my residence wasn't settled (I ended up buying a house, where I work 100% remotely, on the Illinois side of the Mississippi river). My Missouri employer began Missouri witholding by default. The Missouri DOR website gives an example of a Kansas resident with Missouri income that does not have to pay Missouri tax because they work 100% remote. This is consistent with my current arrangement in Illinois, as well as TurboTax's guidance. Nevertheless, Missouri took it upon themselvers to recalculate my taxes and send a reduced refund (not the full amount as calculated by TurboTax). How do I fix this and get the full refund? I submitted an Illinois return in which I paid tax on this income.
