Upgrade of contract without my knowledge

Vodacom, to leave a message on my phone that you have received my Helo Peter complaint and traced the specific matter back to Business department, does not count as "response received" - I have received no solution on my problem after my contract was upgraded without my knowledge. Not from Vodacom, and not from XMnds' Shenies who seems to be the guilty party. I can still not upgrade my device. I WILL stop payment if this is not rectified, sue me for non-payment, you can explain in court then.