Poor service

I had called in querying about my cell phone contract on during the first week of October 2017 spoke to a Miss Nomfundo Zulu and during the conversation she had stated that she had decreased my limit to R50 .However I now just received my statement which states that I used an excess of R500. This is absolutely pathetic from a service point of view!How many times must one struggle with Telkom Mobile I'm so disappointed now I need to pay R500 extra because the individual who had assisted me to open up the account in the first place had not done his job properly and did not confirm these things with me. And now when I try to rectify the matter you guys still don't get it right! And I called you client care center and asked for recordings as proof and could not be helped . So tell me what's the point of having a client care center and why are the people put,in place to provide efficient service not doing their job properly ? Absolutely pathetic - I just want to cancel my contract I've had enoug!