Thank you so much for your answer. Great help. My apologies for the confusing second question. I meant to say “income”.
There is a phase out for the amount you're entitled to, from 75-100K for single and 150-200k for married joint, for every $100 over the lower threshold amount, they reduce the stimulus by $5.
I think this somewhat addresses my concern, but not quite. In my particular case, my client had a total income of $56k yet the full ($1,800) amount was deducted. ( Ie. Client had a tentative refund of $1,500. After I entered the $1,800 stimulus checks now shows she owes the IRS $300. What am I doing wrong????