My NYS return wants me to "Check This Entry: Other Additions/Subtractions Stmt (225): Sch B Part 2 Code-5 is not a valid subtraction code. How do I get past this?

Seems to be related to Form IT-225.  What is that form and why do I need it?  I do not live in NY, nor do I have business there. I am a US expat and haven't lived in the US for more than 30 years.