DSTV dont adhere to downgrade instructions

I have requested twice to downgrade via call centre - did not happen. Then i complained on their facebook page and wanted feedback. Twice. Still waiting. In the mean time my debit order was debited of my account for the full amount. i did not budget for this. they promised me twice it was changed and debit order will reduce accordingly in time. Your service sucks. want to cancel it all together. Anyone out there?