Car Track is ripping me off

my car was written off on an accident in October 2018, but Car Track refuses to cancel the contract, they continue to debit my account even after I had sent them an accident report and a letter from the bank as proof, yes I do understand that it is a contract, but under these circumstances, its beyond my control as there is no car to track. its not like I am cancelling for fun, I no longer have a car, so what is it that they are tracking. please help me Peter!!