billing while done paying

I had a contract with cell c that was supposed to end in June. In March I was told that I've upgraded to a new phone that I've never received. I couldn't cancel the contract with them because they told me I've upgraded. I then decided to stop their debit order because there was nothing happening on the case that they said they are investigating since March up to now. They never call me to give feedback, I have to call them. Even though I've stopped them fr debiting me, they still did this month. I am now paying for a service I don't need nor use. A consultant by the name of Mpho Ndlovu promised to help me but never got any help. Please help