Very poor client service

I was offered credit life insurance. I did agree with the terms of which one was that there is a 30 day cool off period after I receive my policy documents. I did not receive any documentation, the sales person confirmed my details. I requested the policy to be cancelled via email. This was ignored and they rep**** that they did not recognize the email address and that I must write a signed letter with the request and send it to them. They however went ahead and debited my account with the additional amount along with my monthly vehicle installment. I send the signed letter whereby requesting the policy to be cancelled and the debit refunded. No response to date after 2 requests.