Unauthorised deductions and exhorbitant costs

I am living in the UK, let's get that straight from the outset. I have not been in South Africa since December 2012. However, I still have an active current account and credit card with Nedbank. My South African income is erratic and is only coming in every three months. Nedbank are drawing unacceptably high service fees and other admin fees from my current account every month - I'm sick of that, first off. Secondly, I noticed this month that they willy nilly took R204 off my account for 'Greenbacks' I haven't used Greenbacks since I was in South Africa, I have no idea what this is for and I want it reversed. I've sent them a 'secure message' via internet banking. I no longer have a South African mobile phone and my origianl email address (which was tied to a South African hosting company) also does not exist anymore. Nedbank make it impossible to get hold of them when you are outside the country. I've also repeatedly DEMANDED that the Nedbank Credit Card division stop putting ridiculous charges against my CC balance - as I can only pay every three months. FYI in the UK you DO NOT GET CHARGED BANK CHARGES ... why do South Africans put up with this ********?