Cell C
Settlement amount more than contract value

I requested my settlement amount last week Saturday and received received the wrong feedback today (Thursday). I am referring to my cell phone contract, not my data contract. How is it possible that the settlement amount is R1898.62? If I continue with my contract, I am only going to pay R1800? So it is cheaper just to pay the monthly premium and get the air time on top of that. Please give me the right amount. Thank you