ADDING CHARGES TO MY ACCOUNT W/O PERMISSION

I received a call from Vodacom over the December period. I declined the offer for a new cellphone. A couple of days later I received a call from the courier company, standing outside my house with a phone. I sent them back, phoned Vodacom in order to find out what happened. I was told it was a miscommunication. I then received another call, this time the person tried selling me an extra sim card with a monthly data package, which I declined. He then tried to convince me to take it AND a mobile wifi thing to enable me to use the data. I once again declined. Lo and behold, when checking my bank account I see that Vodacom charged me almost double this month, and upon phoning I was told an extra line was added to my account. I've been on hold for 20 minutes trying to sort this out, no luck. THE EXTRA LINE AND INCREASED AMOUNT DOESN'T APPEAR ON MY INVOICE!!! Cheap tricks, Vodacom.