Review Notification of change of Bank Account

Herewith I would like to inform your office that my bank details have change from Standard Bank to Bank Windhoek and I would like my refunds to be paid into my new bank account.
Recently I was refunded for my cancelled policies being funeral and ultimate but these monies have been deducted this month again reason only known by you so I would like to be refunded as soon as possible but in my bank Windhoek account as the standard bank account is no more active.