Ignored Cancellation Requests

Wish I could opt for no star, as they deserve nothing! Absolutely discussing service. My father's now been trying to cancel his insurance for the last 2 months and still they debiting him and ignoring all our requests. Last month I was Informed that it is canceled and they would Put a request in for a refund..... 1st of May came around and once again he was debited and still no refund in his bank account. We've now sent letters, emails, several phone calls to cancel. What more would they like us to do in order for this to be canceled??????