Standard Bank Contact Detail Update Denied

I contacted Standard Bank on changing my contact number as I am abroad. Until recently my SA number was working fine. Nou the number is lost, I need to give the bank my new contact number abroad. Got a lecture on how I should have changed the number before I left. It funny one can not update simple little issues like this online, like any other bank in the world. I WILL hold Standard Bank accountable for any issues with my account. I have an overdraft which I have maxed and currently paying, I can always stop paying, this could always prove it is me. Funny how I owe money, try to do the right thing by allowing the bank to contact me, and get give 200 reasons to not get assistance. Really ridiculous. Dont contact me on my SA number, it is no longer my number!!!