Terrible Service

I requested for my banking details to be changed a month ago with one of the service agents (as i changed my bank), whom assured me that it has been changed. I was also called a few days later to confirm these changes. However, few days ago my debit still went off from the old account in which i only left enough money for my cellphone debit to go off. Because of this, two debits of mine were rejected costing me R115 per rejected debit. I tried to sort this out a few times with telephonic service agents as well as the Twitter service agent but i'm getting nowhere. I was instructed to phone 10217 (which i never get through) or to phone a Fathima on *** (never answers). Telkom leaves me no choice but to consult the Ombudsman on this matter.