Paid up letter overdue request

I settled my access loan on the 28th of August 2018 and was informed that the account would be closed and I would receive my paid up letter on the 04th of September, till I haven't received it and each time I called am being sent from pillar to post. Today when I called I was informed that the account was not closed even though I had received email confirmation from standard bank on the 28/08/2018 saying that the account was closed, after speaking to the consultant she said she would escalate my matter and I received another email that my request will be resolved on the 17/09/2018 am extremely angry as I am done paying my loan off but they are not providing me with my paid up letter as proof.