Unauthorized debits

They failed to address my query on time. They were unreachable. Just when I cancel their contract of 6yrs that is when they come back to me to investigate WHY DO I CANCEL THEIR SERVICE. How bad and cruel they are even after 3months of cancellation they still take money from my account which cost me bank charges for reversal. I just don't know how can Old Mutual tarnish it's NAME by underwriting IWYZE to operate with them.