Cancellation of contract without request

Good Day I do not get any assistance from Vodacom. The cancelled one of my contracts which I did not cancell. They have invoiced me with an amount of R7355-92 for the phone. After several calls i was promissed that the contract will be reinstated and that I will be provided with a new invoice. This has still not be done. It useless to phone te call centre as they just say its a prepaid line they cannot assist. Im really dissapointed as this is the first tme to receive such bad service from Vodacom and I have been a client for many years.