Rude and unprofessional call center

I am utterly disgusted with Cell C. I called numerous times asking the debit order to be changed, tonight I asked that the debit order be put through again, as they again failed to change the debit order. Was told that I am being penalized when it does not go through as Cell C has the right to change the date if they want to if it falls over a weekend. I asked the woman to show me this and she said I must read the contract and she will not stipulate it to me as it is not her job, I should have made sure when I signed it, and the previous people explained it wrong it is my problem, I can sue them. I completely lost it as she is sarcastic and rude and keeps on interrupting when I am speaking and talking all over me. I asked her if she is mad, wanting me to sue them for a penalty. She expressed that she does not want to help me because I am using vulgar language, but her being rude and sarcastic and unhelpful is not vulgar. I explained that I simply asked her a question, does it make sense to sue someone over this? But she kept going on and interrupting me and refused to provide her name, told me I call again and lay a complaint. Encouraging me to complain, making me think it is not the first time she treats people like this and obviously gets away with this and thinking it is fine. Cell C clearly condones their clients being treated like this. Well done if this is the kind of service you provide and the attitude that you condone in your company, is this the training you provide to your call center agents? I acknowledge that I lost my temper with her, however, if she was professional this would not have happened. I am done with Cell C! Never in my life have I experienced such lack of professionalism and sarcasm from someone. Please consider the after service you will receive when signing up with Cell C. Maybe not a good idea at all. I will not recommend Cell C.