You can have an income protection policy through your super, as well as through a standalone policy. To see what (if any) insurance you have inside your super, call your super fund and inquire with them. They can inform you of the steps you need to take if you choose to amend or cancel your cover.
Good to know: Income protection is often far more basic within super accounts, so you may well find better terms and more tailored insurance by going direct with an insurer.