Incorrect Billing

Once again MCA disappoints me. Called in yesterday and no one could advise as to why my amount due is R597,16 rather than R499 which I'm trying to pay. Called in today again and spoke to Masixole and he was clueless and kept asking irrelevant questions patterning the amount due. I'm trying to pay for the price lock amount due and need to know why the amount is incorrect and no one seems to be able to answer. Account number ***0