BAD MISTAKE !!!

Recently had fibre connected to my home and chose MWEB as my ISP . The agreed debit order amount has been exceeded every month to date. The amount agreed was R809 pm - debit order amount on 30 Sept'18 was R1022 - excess of R213, Response from the billing department ''it's not our problem you sort it out with the sales department". Hung on for the Sales Dept. all I got was messages and music, then cut off