Bad service from mtn/debited my account wrong date

I called mtn before the 20 April requested to change debit order dates as the consultant confirmed on the line it was done came 20th they not debited tried calling but couldn't get through coz of the strike waited for month end and still it didn't not run mtn only decided to run the debit order on the 5 and which bounced called them was told to make manual payments and they will refund the amoun that my bank charged me still today im not being assisted ref *** /*** those were the ref I tried calling in spoke to mantoni was told to hold and phone cut she didn't even bother calling back I have tried communicating via email aswel and no one cares im just not happy with the service im getting from mtn contact centre