Vodacom - make it impossible to cancel a contract when the contract period is over

I have been trying to cancel my data contract with Vodacom, when you call the call center on ********** and I give them the number I want to cancel, they tell me I am on the old system and that they will get someone to call me who has access to the old system. This has happened 3 times and I am still waiting to get a call back.

I told one consultant that he must find someone with access to the old system, he put me on hold and 45 minutes not even a I am looking for someone.. every now and again the music would stop as if the consultant cannot believe I am still holding on and the music would start again.

Vodacom are quick to get you to sign a contract but make it impossible to cancel the contract as you cannot cancel at the branch only on ********** and then they tell you it is on the old system and they they will call back and never do!