Absa extended cover insurance useless

I took absa extended cover insurance that is suppose to fix small dents and stretches for my car , but the insurance is useless as it rejected my claim because it was above 2000 rand which they can only cover and now i have been trying to cancel the insurance and when i called their line i was told to send an email which i did twice already but they are continuing to deduct money from my account. They only happy to keep on taking my money even though they are useless when is time for them to pay.