No ... quite the opposite. If you did not get all the stimulus money you are entitled to using the 2020 information then the missing money can be added to your refund.
What can be confusing in the program is that the credit for missing money is added to the refund in the beginning until you tell the program at the end of the interview how much stimulus money you got in advance and the refund is adjusted accordingly. So if you got both of the first 2 stimulus payments of $1200 + $600 and you tell the program you got those amounts when asked then the refund meter should drop by the same amount.
