Unprofessional service from wesbank

I requested a settlement amount for my car account on the 23 September 2025.It was send to me and I settled my account as per settlement amount received.Wesbank send me a letter confirming that I settled the account. On the 26th September a debit order went through my account for the car and I thought it was send already.i kept quiet for weeks and I inquire about the amount that was paid after I settle my account. A good explanation with a promise to refund my money was given.They also apologize for the inconvenience. Aftrr days when I was expecting the money they say they want proof of payment.