Amending Previous Tax returns

Question : I am an international student and wrongly filed  my 2021 tax return as Resident using Tax slayer  and got extra federal refund last year. Now I am trying to amend that using Sprintax, and it says I don't need to file any state returns at the end but my 2021 W2 has state taxes I guess. I am struck with this and any help, suggestions are appreciated.