No Customer feedback despite numerous email, then attitude of "this will affect your credit record"

I was previously on Autopage for my sons contract. I renewed it just before they migrated their client base to Glocell. I am sure i signed for a top up contract, but i dont have a copy of the contract i signed, therefore glocell charged me for additional data. i was on top up before as kids can run up bills. they send me a copy of their computer generated bill, which i couldnt dispute. then there were charges of 250 a month going through in addition to the subscription and phone charge. I queried this and the contract together. When they answered about the contract , I asked them to put a limit on the account, which they said is R50, through the call centre. Again i was charged over and above the additional R50. They still didnt answer what the additional R250 a month was. I stopped my son using the contract and refused to pay subs. I sent multiple emails to the call centre from July 2016 to January 2017. I kept being told it was escalated. I cannot continue to pay for a contract when their customer support is not getting back to me explaining additional charges. I kept reversing the charges. Eventually I told them to cancel the debit order until they sorted it out. I wrote an email to the customer agent again, in point form telling them they they had not answered my query for a year. This is when i was told that It would affect my credit rating and they had answered. No proof can be provided. I said i would still pay for the phone portion, as my son is using the phone, but not the contract as glocell add charges and do not answer questions about what it was for. This is logical, charge someone additional fee and dont tell them why, there is no way you would accept that. Their customer service has been non existent. How do you run a company this way!!!!! Absolutely shocking service, and when your agent cannot even answer a point by point email it is totally unacceptable. i asked for a manager to contact me, but the service agent will not escalate it. also totally unacceptable! Agent is Zanele Zweni . Original complaint about excess charges and data after i had put on a limit, 6 September, first response ---31 March. But i must still pay. I refuse to pay from December to now for any contract fees as you have not held up your end of the bargain!