Incorrect information on my ITC Record

I have been paying my personal loan R2900 every month but august I pay R20000 towards my loan because it shows that I was in arrears of R38000. All of a sudden Nedbank is not updating my ITC record even if is monthly instalments or currently I have tried to resolve the matter, however Nedbank is adamant that I should settle the full amount before they would consider updating my profile. when I check my ITC record that I am having outstanding balance of R71500 but on the loan statement its show that I am having outstanding balance of R48500. can please update my ITC record according to latest payment.