R12000.00 on bank charges from an account I have not used for years.

I opened an student account when I was a student in University, left it after few years of using it probably (2***). And last week I went to the branch trying to open a life insurance with them I was told I owe R12000.00 even though I was not using the account to top that up I was told it was upgraded to cheque account, life for real. R12000 from bank charges wow.