MTN is the ****tiest network provider

Called them a week before the 15th of Dec to change my debit order date to the 15th of Dec as I was going to be paid earlier..it was rocket science for them called them on the 22nd as they hadn't debitted my account I was told that my account my now a month behind so they'll debit in January 2016, I asked the consultant to change my debit order date to the 20 as normal I was told It was done as per my request but that was a lie...they tried debitting my account today and when I call them they say it was never changed. My question is who's gonna pay the the bounce fee of 120 that standard bank will charge me because I won't pay it....MTN is ****!!! They always mess up and no one wants to take the responsibility....I'm fed up. MTN is kaak, may cell c keep up the good of taking MTN's clients!!