You’re question needs
a bit more information, so I’m making some assumptions to try to help. Please add more information if this is not
what you are trying to ask.
It sounds as if you filed a NC return in the past, either
because you lived in NC or worked in NC.
If your situation in 2017 is that you lived in SC all year
and worked in SC all year, then you would only file a SC return. If there was any point in 2017 that you lived
in NC and worked in SC, then you would file a part-year resident return for NC
and a part-year return for SC (either as a resident or non-resident).