Insurance policy cancelation request

I have been having business insurance policy with this company for 3years U sold one if the Fleet vehicle. Fir several times Iam reaching out to them initially through the broker to cancel that vehicle from the policy since the vehicle is no longer in my possession buy they don't want to cancel . I even tried to send emails since I am away from the country to call them and I indicated they can't get hold of me through telephone since Iam not on land I have an assignment by the marine / navy but they seem not to understand they are dragging to actio until another day for debit order to go through Iam.loosing money at their benefit . Iam so disappointed with this insurance company it seems they don't serve clients they serve themselves. I wish I was in south africa I will cancel all the policies I have with this xompany and get another policy