Telkom does not treat there customers fairly

I Ma very unhappy with the service I received at Telkom Blue Route Mall. Since last year November Iv asked them to change my debit order date as I changed jobs I wanted the DO date the 27th of each month but was advised it can only be changed to the 31st. The consultant assured me it has been changed. My DO never went off Dec however it went off of the wrong DO date therefore there was no money in my account. I went back into the branch and was advised the DO was not changed the lady assured me the DO was changed to the 31st I asked for a statement to make payment for Jan as the DO did not go off. I was given an amount of about R349 which I paid at the Checkers money market which I was advised to do. My understanding is that my acc was up to date and that my DO would go off as per normal in Feb. My DO did not go off in Feb and on the 16th March R980 was deducted from my account which I reversed. on the 21/3 I went into the store and spoke to an consultant ( who advised he was the manager when I asked to speak to one),he was not very helpful. he advised the R980 was the amount brought forward from Jan and I incurred changes which was not fault if they had changed my DO as I requested numerous times this would not have happened. I refused to pay these charges as Telkom is not taking responsibility. I advised him the 3 times I came in to change my DO date all 3 consultants assured me it was done and advised they could not give me proof as it was on the system. I advised the manager I spoke to 3 people and cant remember there names but know they werent in the store as I remembered there faces. The manager advised he cannot answer for people I spoke to,and that I should call Telkom disputes which never answers there phones. What kind of response is that . I am furious for Telkom not handling this situation that they messed up and as a loyal customer for many years its disgusting. Im extremely furious and cancelling my contract even though I will be shooting myself in the foot,as they are ******* and just want to make money.I actually wanted to take out a internet package but after the service I got at Telkom I will never do business with Telkom again,you guys are a pathetic company and your customer service sucks