Unfair treatment

Paid my account in full a month ago and I was told that it will be updated on the 12th of this month. I checked and discovered that the account was updated on their side but then on ITC its still reflecting as outstanding. I called requesting a letter confirming that everything is in order and that the account is closed and fully paid and I was told I'll have to wait for few more days. I fail to understand why I have to wait because I sent a request a month ago and I was told I will get the letter once their system updates on the 12th, I was then told that I will get a letter confirming that the account is closed on the 12th of November which unacceptable.