Bad service from Standard Bank

My mom bought a vehicle through Standard bank vehicle finance,but my husband is paying it. The vehicle was paid from my mom's account at first and then changed to debit order from Fnb. After 2 years we were handed over to lawyers for not paying the vehicle. The debit order went off every month, all the proof of payments have been sent to standard bank and still we get told that it's our problem to find the money. It's the worst service we have ever received from a bank.