Problem with stimulus listing on my tax form

In TurboTax as I was doing 2020 taxes, it showed what I got for first round and second round stimulus checks. It asked if the numbers were correct and I said yes.  When I got my refund I was shorted $600 because somehow 600 ended up in line 30. I didn't enter line 30 - turbotax did it for me. So I don't know how it got there. Operator error or problem in TurboTax? I am a dumb user, I only answer the questions asked by the program. I don't attempt to do the numbers on the form. Where did I go wrong?

 

Thanks!