Unauthorised termination of contract

i went to Vodacom Customer care Vodaworld on 25th Jan to request a quotation to settle my handset subscription. i was told that the amount to settle the handset was R700 excluding vat. I paid R800 and the the Vodacom agent sent the Proof of payment to their accounts department with a note on the photocopied receipt \THIS IS TO SETTLE THE HANDSET SUBSCRIPTION. DO NOT CLOSE THE ACCOUNT!"in big bold writing. Lo and Behold i receive an SMS 2 days later stating that my account will be closed on 31st Jan and that i should use up all free minutes. i then receive another sms that my cell number will be converted to pre paid on the 31st.i spoke to Greg Kleynhans (our Vodacom Corporate Account manger) who manage to reverse the cancellation of my line and account. This morning 31st January 2015 i look at my bank statements and see that Vodacom has debited me R848-00. WHY? this is a corporate account which my company pays R500 PM for and i shouldnt be billed. I then download my vodacom invoices only to realise that i am still being charged the handset sub ( R200). what happened to the R800 i paid and why R848 was taken from my account. I have called the accounts department who cannot assist"""