STILL DEBITING MY ACCOUNT

I have been using Telkom data for the last few years. Not only has my contract ended (which they failed to tell me) but December I got little or no coverage at my residence, when I called for help I explained to them that this was only since December. <br> I was told to change my settings to Roaming (which has made no difference). I called again for assistance as well as a form to cancel my data. I submitted the form 2 months ago and it had still not been cancelled and no one has bothered coming back to me they just debit my account. <br> Besides following their procedure, how on earth do you get them to stop debiting your account?