you need to go to that years software and amend the return. You dont need Professional to amend a return, you can do it in Basic.
https://proconnect.intuit.com/community/amend-tax-return/help/how-do-i-amend-an-individual-return-us...
♪♫•*¨*•.¸¸♥Lisa♥¸¸.•*¨*•♫♪
