Wifi contract deal cancellation failure

Good Day MTN , I have been going through a lot with your company for the passes 2 months . I had taken a contract for a new product that was on market and I was the first customer in that particular store to use this wifi contract deal . It did not work from the moment I purchased it and they told me to wait 48 hours so I waited for 4 days and still nothing then returned it to the store and they could not assist neither could the customer service help because it was showing active on their side . Everything was returned to the store within the 7 day time frame and the contract was cancelled and forms were signed , I then took another contract with Telkom and received better service however MTN still tried to debit money out of my account last month for the contract , I’m now stuck with two contracts under my name and one of which I have no use of . I’m stressed as they might try again to take the money this month . The process to rectify this issue is taking way longer than anticipated . Please rectify this issue as it’s not something I can take lightly as it’s debt on my name for something I have no access to .