Incorrect Stimulus Credit

My mother claimed my 2 kids last year and also will be claiming them this year. She received the 3rd stimulus for herself and my son( I received the stimulus for myself and my 1st child NOT my 2nd child because he was born in 2020). For this year, TT is stating she should have received $4200 because its obviously based on the information entered and AGI and when I enter the correct amount that she received(2800) its saying she  qualifies for the recovery rebate credit of $1400 which I know is NOT correct.  We want to avoid any delays so my question is...What amount should she put down; The correct amount that she received....or the amount that TT tells her she should qualify for?