Vodacom not fulfilling what they agreed in their telephonic contract

I got a call from an agent that promised me a Laptop Plus data and my current airtime and data will not be changed. When the contract was changed, all they gave me was a laptop and data and the airtime and sms's were taken away. Now they saying the agent did not provide us with the right detail and they now want to cancel the contract. They are not talking of reparation for taking away from me the airtime i used to get, etc. This is just nonsense