Hi, I am a J1 visa (Postdoc) holder and signed a tax treaty for 2 years. I have already filed my tax return for 2015? and received my refund as well. I filed 1090NR-EZ, but received my 1042S after filing my return. So I didn't included my income and 1042S with this filing. Because I was on treaty so I was 100% waived for my income, but I know the submitted information of income is incomplete. Now what should I need to do? Do I need to file it again? If yes, how should I file the 1040NR-EZR1 as I have already received my refund?