Bad service received from credit card division

Customer service at Nedbank credit card is very bad, I requested a settlement letter on the 17th Sep and I paid it same day. I then called for account closure and have a paid up letter sent to me I am still waiting for the letter.... Instead they are now telling me that account has now accumulated charges which I am not going to pay because i logged a request and I was advised that account was closed I must wait for the paid up letter. At some point I was told that I should not close the account they can freeze the service fees for me which is now making me think that the reason for not closing my account was done on purpose. I have logged 2 formal complaints already but still nothing is being done.