Just slams you with charges!!!

I immigrated to London, my Cheque and credit card were still open with Standard Bank and I had money coming in every month. The one month a payment bounced as I was JUST too short and the very next month Standard bank tried to take double the payment and fees which was too much for me to pay. After the third month Standard bank without warning to ask me to pay up or they will hand me over to the attorneys I just got an email from an attorney notifying me that I will be handed a summons if I do not pay the FULL amount!!? I received no email or phone call to my mother who before I left I went inside the bank to advise them I was moving and that my mother would be the person to contact with any urgent queries. I wanted to pay the full amount and the attorney sent over an excel spreadsheet of the charges which adds up to almost R4000 in lawyers charges!! I had asked this attorney from the start what were the payments i needed to make monthly and how did she come to that amount? She advised me that it was just 10% of the total amount! Which was a LIE!! I absolutely REFUSE!!! to PAY FOR THESE CHARGES DO YOU HEAR ME STANDARD BANK!!!!! You can close my damn account after 16yrs!!!!!!