Incorrect Billing and Arrogance

I upgraded my Telkom Mobile Contract in January this year, I did the upgrade over the phone ( which means i do not have the contract agreement on paper )and specifically asked that my account be capped at the agreed contract amount.I noticed that i have been incorrectly billed and contacted telkom mobile notified them and requested the recording as i wanted to lodge a formal complaint, the refused saying i can only get it if i bring a court order and also that they will first listen to make a determination as to weather indeed the agreement is as i am saying .My understanding is that the recording serves as a contract in the case of telesales until now i am am waiting for the manager to get back to me after i refused to accept that they will first listern and will not provide the recording.