I entered -1 and Lacerte doesn't show additional refund for 2020 tax return.
Do they qualify? There are income limitations and age limits for kids.
Enter what was received for each Recovery Credit in screen 38.2. If one was not received, enter -1 for that payment. This worked for the one return I tried. Remember that the amount is dependent on the 2020 income.
I did that and it didn't work for me. I am lucky that I also use Drake, and it worked fine on Drake tax software.