Account Closure, and Paid Up Letter still not sent!!!!

On 9 November 2018, I settled my loan with Direct Axis. Since they are a subsidiary of RMB and they use a FNB account, the amount surely reflected on the same day. So, on Monday, 12 November I called them to ask for a letter indicating that the account was paid in full and closed. I was advised that it would take 48 hours for the account to be closed up, and I have to call again to request for the letter. I called on Wednesday, 14th November to request for the letter again, and I was advised that it would be closed on 19 November. I do not understand why they have to take this long to close off an account for money which was sent and received on the same day. The thought that one needs to be constantly calling them is beneath me, and find it as an utter waste of my time! Please close the account and furnish me with the confirmation letter as soon as possible!!! I hate the unnecessary admin that I must be subjected to while I have paid all your money in full!!!