Deceased mom & Stimulus

My mom died in May 2020 and I am filing her final taxes.  I answered the question that she received the stimulus in April and $0 in December.  TurboTax keeps entering $600 credit for stimulus in December even after I remove it - which keeps increasing her refund.  It will not let me move forward to file without it.  How can I fix this?  I don't want to have to file an amended later because of erroneous refund.