Standard Bank Vehicle Finance

We are having a horrible experience with the Standard Bank ,they are forcing us to use car insurance ,which we have not agreed to ,We are using our own insurance with PMD car Insurance,and we have sent them proof that we are paying for our own car insurance.,but they keep on harassing us and sending us insurance statements that we have not agreed to,a person by the name of Lee from the Standard Bank Vehicle Finance ,promised that he would force Standard Bank Insurance on us