Pathetic service from Telkom

I took out an ADSL Wifi contract with Telkom last year 2017, the deal was uncapped Wifi for R605pm. I get my monthly statements emailed to me regularly, with all my correct information i.e. Physical address, my name and surname and telephone number. For the past few months the bill has been R643+pm when i called in to query this, i was greeted by an agent who seemed to be frustrated and i was asked numerous verification questions, when i tried to explain the reason for my call/my query the rude agent, furiously stated that the number i am querying is on another individuals name and she could not assist me, i asked how that was possible when i receive my statements monthly with this information on it. i have no way forward as when i go into the store to query this , the store tells me to contact the call center