Useless service

A while back an agent offered me to take up the rim and tyre cover and told she told me that it would be for me to be able to claim should I damage tyres or rims on my vehicle. Last week I called in to claim the agent on the phone advised that the policy had lapsed because I didn't renew it, which I was never told to renew. He further explained that the cover only assists should I want to claim for damages caused by potholes, it covers the administration for me to make the claim to the government, I told him that it's fine I don't need it if it will not serve the purpose of what I was initially told. This month they deducted from my account, but how can they deduct for a cover that lapsed. I had my bank reverse the debit and now I'm receiving sms's that my account is overdue. Can someone contact me to rectify this issue and cancel that useless cover.