It is probably because Degreeworks is showing requirements for a different year than you expect.

Degree requirements are published every year and sometimes change. Under UofSC rules you can choose the requirements from any year after you started at UofSC. By default Degreeworks chooses the requirements from the year you started. You can view the requirements for every year at the Academic Bulletin Archives.

To change the requirements year that your degreeworks account uses you have to contact Student Services. They can make that change.