Terrible service from Mondo/Telkom

I took a Telkom cellphone contract via Mondo in May 2019, and was advised that should I not be satisfied with the package, I can return it within 7 days of receiving it. So I did return it back within that time frame. 4 months later, my account is still being debited. After NUMEROUS calls to both Mondo and Telkom, cancellation has not been made. Mondo keeps telling me that they will follow up on the cancellation, and I will get a call from them in a few hours to update me.

NEVER have I ever received a call, not even an sms from Mondo to update me. I'm the one who keeps calling, and I get the same response every time, regardless of who I speak to. When I call Telkom, I'm told there is nothing they can do as I took the contract with Mondo. When I call Mondo, they tell me there is nothing that they can do as Telkom does the cancellation. I requested for the cancellation departments contact details, unfortunately, they cant provide me with this. WHY DO I HAVE TO SUFFER FOR SOMETHING I DONT HAVE IN MY POSSESSION????? Now this will affect my credit record badly as I have to reverse the debit orders coz I cant afford to pay for something I dont have, and all Mondo could say is "We understand, sorry about that"....really???? I am really frustrated!!!!!!!!!