Upgrade cancelation

Vodacom is the worst at cancelation of updagrades/contracts. I have been trying to cancel an upgrade within 3 days aftet the dsy of upgrading for the whole month of February now. And this morning i get an sms that my upgrade is complete. Every time I called the cancelations department I was told that my cancelation will be escalated. Now its my 4th time calling to check if the upgrade has been reversed i am still told they are going to escalate my cancelation!!! Where do i go to get this upgrade canceled... Someone help me please