billed on closed account

i went in to the davenport branch to close my 1 account and open a new account. i was told it was done, i went back in to the branch to complain and wrote to the customer care centre. i was all this time accruing debt on this account that was "closed" because i was under debt review everything was going off my new account. eventually i was told to go to the branch and sign a closure form which would go to debt review dep , its over 6 months and the account is still sitting there with a big sum on it, i was emailed to say they will meet me half way and i can pay half the amount owing. But its not my fault the account was left open as i requested it many times. then because it was still open it was my main account so when i received a geopayment off 450.00 it went to that account and i can not retrieve it, so i paid 450.00 for debt that was not mine technically. so i cant even fully utilise my fnb perks like geo- payment . no one replies to mails, i have been through so many different departments. i see on my internet banking the acc is still open.