After you file

@paula-o When you prepared your 2020 return you were supposed to go to the Federal Review section and complete the recovery rebate section to enter the amount of stimulus money you had already received.   If you neglected to do that, the software thought that you did not receive any stimulus money at all, and added some stimulus money to line 30.   When the IRS cross checked, they discovered that you had, in fact, received money and they recalculated your refund--because you cannot get the stimulus twice.

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