Hey Thais,
How did you file both W2 and 1042S?
I have the same case this year, and would appreciate any advise.
Until Oct 2020 I was a nonresident alien and received salary free of federal tax (treaty between US and Poland) - this is stated in my 1042S.
I also got W2 as from OCtober on I paid tax.
Sprintax does not allow to file anything, in TaxFreeUS there is no 1042S option.
