Upgrade Error and no refund

I recently did an upgrade online and was sent 2 cellphones. Due to a technical error they did the upgrade and also took out an additional contract. I arranged to have the new contracted phone collected which was done 2 days later and was assured that the line would be cancelled. I was then charged and money deducted from my account for this line. I have contacted the Call Centre 6 times! My last attempt the agent transferred me back into an IVR queue without any explanation! A mistake made by Vodacom that no one takes accountability to fix . To this point I’ve been told that the line has still not been cancelled and no refund in sight!