Incorrect billing

I have been having endless problems with vodacom since my account was moved from nashua mobile, one of my contract with nashua mobile was R99 but vodacom debited my acc R144 for the same contract but I let it slide as the contract was about to expire. I decided to renew the contract in June with the same R99 deal and i asked the lady who processed my upgrade twice to confirm if I will only be debited R99 for this deal and she confirmed it but to my surprise my bill never changed even the one to be debited end of August still reflects as R144 and i only found out today that vodacom decided to bill me for the sms bundle which was free and part of the R99 deal that I signed with nashua mobile without even making me aware of this adjustments and what really shocks me is that they continue to bill me for this bundle that that i never agreed or signed for even after I upgraded and I would like to be reimbursed because I never requested or signed for this bundle.