FNB not updating credit bureau - for MONTHS!

Experian is showing an FNB loan as 8 months in arrears, when it was paid in FULL in August this year. I have repeatedly requested that it be changed, have had phone conversations and sent around 25 emails to my private banker, the loans department, the complaints department and via Hello Peter (I already posted her a few weeks ago with promises to escalate) but nothing has changed. Every time I email or post on hello peter, I receive an email or call, with someone telling me they have escalated to the relevant department. Still it doesn't change, and I go through the whole thing again. I expect I will receive the same stock standard response to this. "We acknowledge your complaint bla bla and have escalated to the relevant department bla bla bla". Let's see.