Can't I Change Filing Status to Qualifying Widow

My spouse passed 9/2020. I filed a joint return for 2020 taxes, no problem.  I want to file as Qualifying Widow for 2021. I have two dependent grandchildren who lived with me the entire year (actually all their lives). My spouse and I have always listed them as dependents on our joint taxes, as I did again last year, because we provide all their care.  For some reason my Turbo Deluxe says to file as Head of Household because "you do not have any dependents who have lived with you the whole year".  I have answered the question to reflect they have lived with me the whole 2021 year, and try to enter my filing status as Qualifying Widow but the software keeps defaulting to Head of Household and won't allow me to change to Qualifying Widow.  Am I missing something here?  What should I do?  Thanks.