Smoke the client for all they can

I have been trying to have the monthly debit order cancelled, as I wish to make 52 payments per year, as opposed to 12 payments. This way I would save quite a bit of money on interest. Of course SA Homeloans refuse to allow this, stating that every account MUST have a debit order in place. They also refuse to consider an alternative option of a weekly debit order. I think it is disgusting that a company will not allow a client with a perfect history of paying their account, to save money. So much for giving a **** about what is best for the client!