FNB deducting funds from account without paying traffic fines on the Nav-igate LIfe app

I paid my traffic fine using the Nav-igate Life app on the FNB Online banking app. Money was deducted from my account. However the fine is still unpaid as per PayCity. I reported the problem to FNB approx 2-3 weeks ago and followed up with various emails and visits to the branch. FNB has not yet addressed the issue or refunded the money. FNB has also not been able to provide proof of payment, although money was deducted from my account. Extremely poor response and unwillingness to resolve an obvious error on their side.