They refuse to terminate my short term insurance

Do not bundle your vehicle insurance with your car finance. My car is financed through Wesbank but they offered me insurance that is underwritten by auto & general, but it all comes off as one debit order.

I got a better offer for insurance and gave them notice to terminate my insurance with them. It’s been a headache. They refuse to comply and are making sure that they make it impossible to stop my cover. They reply to emails late and keep requesting things in bits and pieces. Almost as though they are trying to run out the clock for my debit order to go off in the next month. They requested proof of my new insurance (FNB) which I did and they aren’t bothered to read the welcome letter which has all the information they requested, which they claim is insufficient.