Demanding payment for cancelled contract

I had a 24 month data contract with Cell C that expired after 24 months. I never gave authorisation for the contract to be extended, now Cell C are continuously requesting payment by debit order for this contract and then phoning me when I arrange for the debit orders to be returned.<br> <br> I feel at the moment that Cell C is harassing me as:<br> they had the obligation to contact me after 24 months to enquire whether I wished to continue with the contract or not<br> they are now claiming that it was my responsibility to cancel the contract and I deny this. In terms of the CPA the service provider has to contact the client, not the other way around.<br> <br> I find their practices ********* and ******* and if this matter is not resolved I intend going to the Ombudsman or one of the bigger newspapers<br>