Bad Service and unacceptable response agent!!!

I need help with the lack of service from VODACOM!!! I have a contract with them which expires now in October and they have now decided to cancel the BIS on my contract which they now tell me was a complimentary addition to my contract?! I have been calling since yesterday to try and resolve this matter with no luck. Yesterday I was told by the call centre agent that she would reactivate the bis. I called back at least 5 times last night only to be told with my 5th call there is a network problem and I should be patient. It is now Thursday evening and the phone is still not working!! I called back now again only to be advised that I cannot buy the Bis prepaid as it is a contract. I must add it to the contract and they will bill me!!! I asked the call centre agent who's name is \Innocent"to please get his manager and he refused telling me he already explained everything so why do I want to speak to a manager and by the way his manager has gone home already!!! How do I resolve this? I am so frustrated I cannot use this phone and it is leading to a loss of income for me. PLZ help!!!"""