Bad service

I went to the Vodacom branch inside Waterfall Mall next to the Pick and Pay to get a letter from them so I can give it to my bank that states that I don't owe them money, witch I dont. First the consultant helped me and she went out of her way to help me try and get this letter from Vodacom but she also failed due to the bad service from the account department. I wrote them and email and explained why I need this letter to clear my name with Experian Credit Beraue because I had to find out by the bank that I have a bad name and can do nothing on my name because nobody from Vodacom phoned,text or email me to tell me I must cancel the contract myself after the 24 months has past so I phoned the credit beraue and ask were can I get the letter and they said I must go get the letter at the shop, I went back to speak to the manager who's name is Nicole and explained to her everything and we got into a argument and said she is not allowe'd to give me a letter she then stood up and left me who is/was a customer for 15 years sitting there. The worst part is that she didn't even put in an attempt to help me get a letter. This was the second time now that she did nothing for me the customer!