******** account debit

Standard bank processed a home loan debit order twice at the end of September 2019 and i am still struggling to get the one debit order reversed. The private banker I am assigned with is absolute useless and never gets back to me (after confirming that it was standard bank the processed the debit order twice), why give me a private banker if I can't even get hold of her????? Really bad service, and this being a homeloan it wasn't a small amount that was debited twice. What about the interest on the amounts ********LY debited?