Bad and *********** service. Vehicle settled but suddenly owing.

Early January 2020, I contacted Sasfin to send me a settlement quote. Which I received the letter on the 16 January 2020 from Petrus Morobane. I then made payments of the amount on the 29 January 2020. In February upon following up I was then told that I need to make another payment of about 2k which I immediately paid. A few weeks later, I was then contacted by someone from the bank informing me that the vehicle has been paid off so all is in order and should I need a new vehicle I should contact them. Since then I've been waiting for documentation confirming that the vehicle has been paid. On Thursday 7 May 2020 I therefore received an email from Petrus Morobane informing me that the account is still owing 28k that a debit order didn't go through. Now something is totally wrong because this account has never been paid through a debit order at all for the past 5 years now, whose account did they debit? And why is it only coming up now after 4months and all the confirmations that the vehicle was paid off? It makes me think that recons aren't done monthly for accounts because now this account is now owing 32k cause of interest meanwhile I'm sitting back knowing my vehicle is paid. I need this to be sorted out ASAP. I've been calling your lines and no one picks up the phone. I'm totally disappointed by this kind of service from Sasfin. Is this how you treat your clients?