TELKOM OVERCHARGE

I paid my account on the Telkom website... more than 48 hours before the debit order was supposed to go off. I was told by the consultants that the debit order won't go off is i paid more 48hours before, but yet i went off, I didn't have money at the time because i thought that it won't go off. I got charged with bank chargers for rejected bank charges,... now telkom is charging me for Payment not provided for, yet i paid the full amount. This is the second time charged for it, but having paid for it. Payments are due before the end of the following month but I'm being overcharged despite being paying whats due.